Given the amount and volume of software that mac has, the fact that almost all new interesting stuff are released for mac first or even mac alone, I also don't think it needs to attach itself to bigger names for platforms.
I think the financial burden of Ubuntu Mobile, Unity 8, and Mir; and the immediate rise of docker and WSL made canonical fully shift to server, so much so that their website no longer is about a better os for people, but what can it do for your cloud. Other distros also followed its path and Linus became all in on servers and IoT. I see windows as the biggest pile of trash in the world. Infinitely inconsistent, buggy, patched worked, visionless and rotting. Honestly that is one piece of software that is worse that AI slop.
And so what is there for Apple to compete with honestly? Haiku? Solaris?