I don’t know why Antergos has less of an issue with handling multiple DEs than Ubuntu does, but that’s just been my experience having used it all these months.
If I had to guess, I’d say its because Ubuntu does a lot of patching to upstream packages. (Meaning they make changes to the code that are not included by the upstream developer). They do the patching in an effort to improve the overall experience which in most cases it does improve things for Ubuntu users. It’s likely that the changes they make through patching are not designed to be desktop agnostic. They expect you to be running one edition of Ubuntu which includes a single desktop. With Arch, patching is only allowed when it is absolutely necessary (meaning the package will not run without it). That policy means you are using the packages as the upstream developers intended them to be. Again, that’s just my best guess. I could be totally wrong.
You know, I actually looked to see if there is a way to get an email notification without commenting, and I didn’t see any option for that in settings, nor do I see anything anywhere in the threads where there is any sort of a “Follow” button or anything like that.
Click the little settings “cog” on the main post of the topic and add it to your Favorites. (Favorites= Subscribe)