This is exactly the view I hold too.
I viewed them as a guided learning curriculum to keep me focused whilst learning AWS. Otherwise, i'd have drifted off down deep rabbit holes playing with some of the more exotic services and missed the 'boring' but most useful services to learn about.
Have previously held, CDA and SAA but haven't bothered renewing them.
Are they worth it in terms of forcing you to study and learn a broad swath of an important technology ecosystem? Well, would you do it without the cert? You might, but having a test to study for helps focus my efforts. This is the source of most of the value for the associate certs, in my experience. AWS is so sprawling, so even knowing that something exists is valuable. And studying for a cert can force you to learn that.
Are they a differentiator for you? Depends on your experience level, the job type, and the competition.
Context: I taught AWS courses for a while a few years back and held 4 certs at one time. Now I just have one (Solutions Architect, Associate), that I've renewed a couple of times.