I've been in two FAANG companies and I can tell you know - go back to startups. I came from startups and couldn't wrap my head around how slow things are. In FAANG everything is promotion driven so people spend most of their energy reverse engineering the system and choosing work that will help them get promoted. It's a never ending, beautifully designed rat race. You will spend weeks on performance reviews, evaluations and other HR corporate mambo jumbo. If you spend more than 50% of your time on actual work you are lucky.

If you have a startup mindset you should go back to startups. You will be more productive, happy and grow faster.