The new guidance is still very much "office centric" and requires that everyone be in the office 3 days a week. And even if you do get an exception to work remotely (which will probably be extremely rare), you are still required to live within commute distance of your assigned office. That defeats the purpose of remote work for a lot of people.
I can do a two-hour commute (especially if it can mostly be by rail) once a week or so. But much more than that and it gets pretty painful. Mind you, some flexibility is better than no flexibility but it's not remote work by any means.
Many parts of it can be a bad place to work. But it's a huge company. There are some parts doing cutting edge work as well that you won't get access to at other companies. But to your point, the likelihood that a junior engineer will get access to that is slim, and so your assertion holds.
Amazon's policy is exactly the same as Microsoft. Is Google proper remote now?