The thing for me is no one benefits from the lack of commitment to some way of working (and I mean a company commitment to something isn't a cast iron guarantee either). It's not like saying we're an in office company we expect you here 5 days a week; for me that would be a massive disadvantage. However, I can see that for other people that would suit them perfectly and might well have lots of advantages in terms of social life and opportunity to learn from those you work with. If a companies stance was that we are working from the office but reserve the right to work fully remote at some unidentifiable point in the future that would similarly disadvantage those people who seek out in office jobs.
> The thing for me is no one benefits from the lack of commitment to some way of working
Amazon would be the one benefiting, because it means they can bring in office working in the future without contractual changes.
Which is totally fine, and means this working arrangement isn't for you, but it doesn't mean it is fundamentally unfair or that it wouldn't work for someone else (like you say - it could suit someone who isn't you).
To me though, you seem to say "this is unfair because it wouldn't work for me".