You're conflating several different things: patterns specifically recommended by the React team, patterns in vogue in the community, specific libraries from the community, and actual API changes in React itself.
This is fair, but I'm not sure how much it matters.
In reality, we build software as part of an ecosystem. Even if the foundation of an ecosystem remains stable, much of the value often derives from what is built on that foundation. It's the other tools. It's also the blog posts and forum comments and training courses and YouTube videos. It's also the collective experience of the community in using those tools, which is reflected in all of those sources of information, as well as simply passed on from one developer to another in person.
I'm not sure React can truly claim to be stable any more, though it's certainly done better at that than many projects in front-end web development. But even if that's true, the community has moved on from the older APIs to the newer ones. The new resources are built using the new APIs and written about the new APIs. If you're still using the older version of things, even things that React itself still intends to fully support, the reality is that you're going to be excluded from many opportunities elsewhere in the ecosystem.
Why would you want to use the old APIs for new code? Surely the benefit of API stability is that your old code that you don't want to change still works? It's not like they're introducing new things every week. It's more like once a year there are major new features, and the old ones still work.
Why would you want to use the old APIs for new code?
Consistency. A code base that has been maintained for several years but now does similar things in four different ways because of which APIs were fashionable at the time each of them was implemented isn't going to be great to work with.
Or maybe you just liked the old APIs better, perhaps because they were more helpful for your particular application than the new ones, or because some other tool or library you find useful works better with the old API.
This is fair, but I'm not sure how much it matters.
In reality, we build software as part of an ecosystem. Even if the foundation of an ecosystem remains stable, much of the value often derives from what is built on that foundation. It's the other tools. It's also the blog posts and forum comments and training courses and YouTube videos. It's also the collective experience of the community in using those tools, which is reflected in all of those sources of information, as well as simply passed on from one developer to another in person.
I'm not sure React can truly claim to be stable any more, though it's certainly done better at that than many projects in front-end web development. But even if that's true, the community has moved on from the older APIs to the newer ones. The new resources are built using the new APIs and written about the new APIs. If you're still using the older version of things, even things that React itself still intends to fully support, the reality is that you're going to be excluded from many opportunities elsewhere in the ecosystem.