It absolutely reflects reality in that school teachers are statistically way more liberal than the population average: https://www.pacificresearch.org/why-are-teachers-mostly-libe... .

These are actual videos that teachers have put on tiktok themselves. Some of it may be performative, but even the fact that they think putting something like that on tiktok is a good idea, speaks to their professional qualities.

I think it reflects the reality that specific groupthink is both tolerated and encouraged in school while other groupthink is harshly penalised.

When the allowed groupthink in question only has support among a minority of the population you can't be too surprised when the rest try to avoid it.