What does explain the the community would be deliberate fraud. A cult lead by James and Peter about an mythical being.

It's a lot easier to convince people you're the successor to the of some kind of deity rather being some kind of deity yourself. A LOT easier. Also... sets up plausible deniability if things get caught out. "I DIDN"T KNOW, HONEST....! he duped me too!"

That’s a long way to go in very little time - that’s only maybe 3-4 degrees away from the original source. Not nearly long enough for a mythical figure to develop organically

It went down in 79AD, a fully 43-46 years after the supposed events and at least 41.5 to 39 years after Paul began his missionary trips across the Roman Empire. To be clear you are arguing a strawman. I believe Paul was real and I believe James was real. I think it was a con job. This wasn't a myth that organically made itself, this was centuries of Jewish legends/stories/culture that was hijacked.

Also I asked for contemporary source not hearsay "3-4" times removed.

You can dispute the details, but someone must’ve been the figurehead at the very least.

Sure they had a mythical figurehead. It would explain why the Romans left them alone for decades after the supposed events. They were running a mystery-cult / charity organization and were saying that their leader had already been killed. Also would explain why Paul didn't know pretty much anything about the details.

The gospels themselves hint at the events being staged to some extent by a small group spreading an ideology according to a literal plan - the public events literally start with Jesus’s cousin gathering support for the movement, and then Jesus goes around recruiting specific people as apostles

Could be. I admit I hadn't thought of that. I promise to look into it. I assumed that they were sorta reverse engineering the "known" events. Building a narrative after the fact, a retrocon.

The Romans also kept records - there’s a lot of corroborating evidence for certain events spread too far and wide for a pre-information age society to fabricate. Even things like his birthdate - I think they’ve been able to narrow it down to a few days in July, during the census, where we had accounts of a temporary new star in the sky

And those records don't show anyone by that name in that city or being crucified. As for the star thing keep in mind the Gospel writers were multiple decades later well enough time to fit the data to the narrative. The census is a classic example of this. It was known that a census had been done around that time it was also "known" that Jesus was from Nazareth but was supposed to be from Bethlehem so the census is given for the reason.

Even the papers that are given clickbait-y headlines like “historians dispute the existence of Jesus” generally dispute certain aspects, there was almost certainly a historical figure named Jesus who was killed by the Romans for inciting a resistance movement

I don't care about consensus or other writers. I care about evidence. Please present it. You gave me evidence that there were Christians decades later, which is not what I asked for.

Roman Jewish Historian Josephus.

Repeating stories he heard decades later. Hearsay by people who had an incentive to lie. Josephus also said things like this:

Now Adam, who was the first man, and made out of the earth, (for our discourse must now be about him,) after Abel was slain, and Cain fled away, on account of his murder, was solicitous for posterity, and had a vehement desire of children, he being two hundred and thirty years old; after which time he lived other seven hundred, and then died. He had indeed many other children, 1 but Seth in particular. As for the rest, it would be tedious to name them; I will therefore only endeavor to give an account of those that proceeded from Seth. Now this Seth, when he was brought up, and came to those years in which he could discern what was good, became a virtuous man; and as he was himself of an excellent character, so did he leave children behind him who imitated his virtues.

It's interesting to me that you consider him a valid source for one thing you can't prove but reject pretty much everything else the man said especially since you can't really disprove the Adam and Eve story.

Enough so that secular historians consider the person known as Jesus of Nazareth to be a historically real person

Interesting because your boy Josphius was in the area and wasn't aware Nazareth even existed. In any case truth doesn't depend on how many people assert something.

His ministry wasn’t even that uncommon at the time. There were many apocalyptic preachers around that time and other magicians/miracle workers, like Simon the Magician.

And?

We know this because a group of followers doesn’t just form and grow without someone they are following. The entire teachings of everyone within his group revolves around Jesus, and if he didn’t exist then Christianity never began. People need a leader to form a group, they don’t just all be together and say hey, let’s make up a dude and then follow what we made up. They believed enough to die for their group, and they believed enough to dedicate themselves to growing it. That doesn’t just happen if you made it on a whim or made up a key point of your story which could be validated. Additionally just because books were written multiple decades later doesn’t mean that they were completely made up. People can live multiple decades, and stories of experiences and knowledge of people can survive this long easily too. We also don’t know what they knew at the time because lots of information about Jesus that would have survived had been altered much much later by kings who wished to use Christianity for control, we of course know he didn’t completely make up Jesus as there are books referencing him from before this happened, however it does mean our information now is more limited than theirs, so we can’t assume they made this up based upon the same information we have now. It is both logical and just true that they would have had access to more valid information than we do today. They where also often scholars who’s job it was to write about true people and to prove together missing info and validate this sort of thing is even real. With all the information that was available at the time they still believed he existed. We can’t say just because such evidence was lost doesn’t mean that they all came to an invalid conclusion or all made it up. It’s just illogical. As for actual biblical events that had few witnesses, it’s fine to believe that that was made up, or information was lost so it was believed that something happened when in reality there is an entirely different reality that we just don’t have what we would need to piece together today. As we are assuming many stories are being made up or are incorrectly accounted throughout it, it’s not fair to say any events in his life happened based on the book alone, so this a mute point.

TLDR Jesus was real because he formed a group that still exists and followed his teachings from the beginning. Groups don’t just form and follow a fake persons teachings and still believe it and constantly lie about his existence. Scholars closer to his life who had more information than we do now believed he existed, and we can’t invalidate multiple scholars with more information than us just because we don’t have that information anymore.