They'd have had a field day with a situation that played out when I was in my 20s.

One girl I went to high school with, who was a few years older than me, had a big crush on the new young science teacher that started at our school in her junior or senior year. She took his classes and was friendly and close with him, but as far as I know, nothing inappropriate happened, and he was absolutely, positively, strictly professional the entire time.

Then she graduated and went off to college and they stayed in touch. Again friendly. Maybe less "strictly professional", but certainly not romantic, even though anyone who knew her knew she had had this crush on him for years at that point.

After college, or even later in her college years, they start hanging out...as friends, maybe as casual dates, idk. Then after she finished college they quickly started dating, became a serious couple, and eventually got married and started a family.

Was it weird? Sure. But was any aspect of it inappropriate? Ehhhhh...idunno. I don't think anyone ever "crossed the line" at any point, but comments were definitely made, eyebrows were raised, and rumors ran wild.

But in the end I think they kept it kosher enough, and by the time they got married, I feel like most people had gotten to the point that their reaction was more or less, "Yeah I guess it's kinda weird, but whatever. It's none of my business and if they're both happy, good for them."

But the kind of people you're talking about would've had a meltdown.