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.
