Charitably: a wider userbase on desktop means there's more attention given to consumer hardware support, vendor/driver support, app support, desktop environment

Charitably: a wider userbase on desktop means there's more attention given to consumer hardware support, vendor/driver support, app support, desktop environment and distro work, etc etc, all of which makes the experience better for the people who already use it on desktop. So I think that's a good reason for them to be excited