I believe you may be not thinking outside your bubble at the rest of the world. You're actually looking at one single vocation in one single area at one single point in time and assuming that therefore all millenials should have no trouble saving that up, totally ignoring that not even most tech sector workers earn that, and the vast vast majority of millenials are not tech workers?
When I went to college only a few years ago the best paying jobs in consulting and banking were largely gated by what school you went to. Now students from “non-prestigious” schools or no formal schooling at all have a good chance at earning that much.
Again, if you move to the right bubble with the right education at the right time. Are you arguing that any millenial that wanted could get that education and move to SV and get a job that paid that much? Does FAANG have unlimited room for developers?