I myself am a highschool student. I go to school in a Likely D county that swung strongly democrat in 2016 and 2018 and my district encompasses mostly Lean D precincts that swung strongly to democrats both those years.
(1) This school is overwhelmingly Republican, and that title extends from disgruntled Never-Trumpers to Turning Point America and PragerU addicts to the, uh, you know. Of course there are a lot of democrats but I would say that a plurality if not a majority of my peers are right of center.
The overall mood among students is a disliking of Trump's personality but support of his policies. (1) There is no liberal group here but there is a Young Americans for Freedom group (which I am a part of) which has about 70 members, and most of them are actually female surprisingly. I will say my school is mostly white (about 75%)
(2) but it still goes to show that from an insider perspective, the "Gen Z is liberal" meme is bogus and is being pushed on us without a basis.
You admit to being in a bubble (1), yet use that as anecdotal evidence to generalize to the political inclinations of an entire generation of voters that exist outside that bubble (2).
Nothing suggests what you claim as a general phenomenon.