There's plenty of people that are relunctant to open up to others because they are scared of their reaction. I am one of them.

And why would you be ridiculed and scorned for opening up emotionally?

because people are mean and repeat the mean things that have been done to them, and difficult emotions make people uncomfortable and one way to avoid them is punishing people who do open up

Sigma > Alpha now apparently, Alpha is the new Beta

My parents and school teachers and peers made it very clear to me that if you show emotion such as sadness, jealousy, frustration, fear, or anxiety, you were not living up to being a male and thus are weak and deserving of punishment, physical violence, and social isolation and ridicule.

why would you be ridiculed and scorned for opening up emotionally?

Not to sound like a blue-haired liberal, but at least in my neck of the woods, toxic masculinity is to blame. Like, one of my favorite internet folk got bullied off the internet recently for saying he likes girls a little too enthusiastically. Some dudes will absolutely tear you apart if you are a man that exhibits anything other than stoic passivity.

I had to Google it and what came up seems to be it's basically a lone wolf but worded by people who also use terms like alpha male.

I may be wrong though.

This would have been a much better meme.

Sigma Males are what those guys who used to call themselves Alpha Males now call themselves, because everyone started making fun of them for calling themselves Alpha Males.