The problem here is simple; it only provides this immense value if it is effectively free without discrimination. But of course, it can't really just be free, or at least Dockerhub certainly can't be.
On the other hand, it also provides immense value to enterprise and even smaller customers, too, clearly. And I don't think anybody ever strongly doubted that aspect, it just was more doubted whether you could make a business out of it. But lo and behold, Dockerhub was integrated enough into the ecosystem and without an a strong enough alternative that it didn't seem to matter.
I assume Docker Desktop also factors into this somehow, but I don't know. I don't use it. Even on Windows and macOS, in the event I must use them to do dev work, I just use Podman Machine. Works well enough for me, and I don't care about a desktop UI (although apparently a couple do exist.)
I am glad that at the end of the day, I haven't seen any super bad fallout from this. I'm still able to use Docker images on my NAS without paying a monthly subscription. Whatever their rate limit is, I'm not hitting it. I'm sure it's a super bad pain in the ass for certain parties though. Like I bet GitHub has a deal to keep Dockerhub unlimited in it's CI, but smaller providers that do CI like srht are probably screwed. That's a shame for the entire ecosystem.