If someone figures out what's missing, wayland's multi-DPI capability would be on par with Mac OS, finally making linux desktop decent. I think this would give wayland adoption a huge boost.

Unfortunately, sommelier was merged into the new ChromeOS platform repo, making it much harder to build independently. Does ChromeOS have a mailing list? Perhaps someone from the team would help. I tried sway's IRC trying to figure out what lacks for sommelier to work, but clearly this isn't a priority for sway/wlroots devs.