Facebook: local employees are expected in the office "at least half the time." But Zuckerberg is quoted elsewhere as saying he thinks a majority of the workforce will eventually be remote. Remote pay is adjusted. Do not know if employees or teams can just arbitrarily choose that setup.
Apple: 3 days in the office (postponed 1 month)
Amazon: 3 days in, 2 days at home as "baseline."
Netflix: 9/2020 articles suggested bringing everyone back full time. Hastings was quoted then as being against home/remote including a joke that he though the RTO deadline should be "12 hours after a vaccine is approved," with the serious followup thought to be after a majority of their employees were vaccinated. That was a year ago and things are more relaxed now; it sounds like it will be voluntary in the near future.
Google: "hybrid" 3 days in, 2 at home for local employees. Some fraction of the workforce will be remote.
Extending to honorary FAANGUM:
Uber: 3 days in, 2 at home
Microsoft: different "hybrid." Microsoft seems to be the only one of the group to have committed to generally allow employees to choose?
reminder those may all be outdated, this was a very quick search. Aside from Apple all the articles were written pre-Delta in the US.