What's a Linux phone? Linux isn't hardware and it isn't an OS. It's a kernel — which Android uses. Android is really just another Linux distribution (as in, distribution of software that makes up an OS that uses the Linux kernel). It just might not be very desirable to the FOSS crowd. GrapheneOS being more privacy concerned, I would say that's more of the target "Linux phone" than a new distribution, but, Android basically exists because Steve Jobs said he could get OS X running on a phone, so Andy Rubin basically said "bet" and made a Linux distro for phones. In very simplified, layman's terms.
So, "the year of Linux" was like, 14 years ago when Android really hit its stride in 2012 or thereabouts. Linux heads wanted people using it on the desktop, but the desktop was becoming the family computer; you either had a Mac (lite) or PC (running a commercial Linux with a Java environment for apps) in your pocket and that was your PC, and has been since.
But if you have any phone, it's doing things you may not like. Android is obvious. Apple says they protect your data, but even if that's true (or partially), for how long? They're trying to break into services. Fortunately, the bean counter CEO is out in a few months, to be replaced by a hardware guy/engineer, so maybe that makes things better? Who knows. And then you have people who don't want either Apple or Google in their phone, they use something basic, but a lot of bank apps and whatnot say you have to be on one of the main platforms. That's one reason I have both.
I sure wouldn't mind if my next Android phone was a Pixel running GrapheneOS, but I feel like that would limit my options.