The announcement from 2019 is https://snapcraft.io/blog/chromium-in-ubuntu-deb-to-snap-tra...
> Simple: they decided that maintaining the chromium .deb takes too much effort, and that snap is making that easier. So they moves it to Snap.
Their whole distribution is copied from Debian. Is it too much effort to just copy and distribute the upstream package, like they have been doing from the very start?
See the link in the sibling comment. They don't copy.
No, they've got to meddle and mess with every damn thing to create unnecessary headaches for users.
Simple: they decided that maintaining the chromium .deb takes too much effort, and that snap is making that easier. So they moved it to Snap.
But there are many users out there with existing installations who have selected chromium as one of their installed packages. And so as not to keep said users without updates, they decided to migrate them over the best way they found.
I'm not completely sold on the snap ecosystem because of some technical issues, as well as the issues of fully automatic updates. But this particular question has been given a lot more air than it deserves.