When reading this, it feels like the goal of those projects have derived?

For me, the "goal" of mainline GNU/Linux smartphones is that we get like PCs. I prefer fedora, you prefer Debian, they prefer Slackware, all is well, we are all free to choose whatever we want for our computer.

Here I'm reading it's all fragmented? And if it's fragmented, I guess it means it doesn't rely enough on Linux drivers, so long term support won't be there?

Is someone "wrong"? Like Librem is saying they are going mainline but actually aren't? Or is it Pinephone? Or I'm misrepreaentating what mainline should mean?