When you realise they are using computers and AI to estimate your level of humanness before deciding whether or not you are human enough [to pass the capcha].

Our humanity is up to machines already

That's one way to look at it. However the more correct way imo is that captchas are there to estimate the level of machine-ness instead.

in the end, it's restricting their access, not yours.... so you might as well think of it as the human gestapo oppressing the bots and cherry picking the humans as the master race

and you know why this happened in the first place?

because our "humanness" is so awful that we created bots doing harmful things in the first place.