I could be the maintainer for the Pixel 3A XL model as I would like to help speed up development of the project. My main priorities would be fixing the battery and creating a prebuilt image so more people can get involved.
I would love to do that, but my skillset isn’t quite there.
However, I have been looking into maintaining a few LineageOS builds for devices that I have which are no longer maintained officially. That’s something I guess.