People keep saying this, like too much effort is a bad thing. But OP makes it clear that there's very little duplication of effort in the Linux-on-phone/mobile/SBC community - most developments are shared community-wide. There are some technical divergences (Alpine/musl vs. glibc- and init-based systems for example) that can impact direct compatibility, but they're very minor.
People keep saying this, like too much effort is a bad thing. But OP makes it clear that there's very little duplication of effort in the Linux-on-phone/mobile/SBC community - most developments are shared community-wide. There are some technical divergences (Alpine/musl vs. glibc- and init-based systems for example) that can impact direct compatibility, but they're very minor.