Google, Meta, Amazon & microsoft all do banding, so the base wages is mostly public (hence why its all bollocks about wage negotiation, there isn't any.) The first level of senior for most of these orgs will tip the scales at around $300k
Having worked at both startup and FAANG, I don;t think startups actually give you the skills to flourish here in corp land. Sure, you might be a good coder, but most of the time its navigating politics that actually gets you promotion (that or good luck with a successful project)
You really don't need to be a good coder to be at a FAANG. Sure there are specialisms as you point out. but most of the time its just entry level CRUD, followed by manic debugging with shitty non-documented tools.