Earlier quoted context omitted.
Plenty of android phones have alternatives. It's what custom roms in the title of this article is referring to.
But these custom ROMs are hard to maintain especially as soon as when the phone manufacturer drops support. There's no way to get the latest AOSP on these devices forever. Hard work is required to port any new version and that's not always possible because AOSP comes to rely on newer kernel versions but you are stuck with the heavily customized one (+ the blobs) the manufacturer provided.
Of course you need to choose a supported phone, but these days there are plenty. And those alternative ROMs are getting really, really good. I have been running /e/OS for two years and I can't tell you a single thing I cannot do because of that (maybe a banking app started crashing once, and after I updated it, it was fine?).
The biggest thing really is that instead of Google Maps, I use one of the awesome OSM apps (Organic Maps and OSMAnd, in my case). And maybe it takes a little bit longer to get a GPS fix (I'm talking a couple of minutes, sometimes).