While there's a huge focus on Flatpak and Flathub thanks to the Steam Deck shipping with it out of the box, Canonical on the other hand continue with their own Snap packaging and they have a Steam Snap in testing for Ubuntu (and other distros, since Snap also works elsewhere).
In a fresh introduction post on the Ubuntu Linux Discourse forum (thanks OMGUbuntu), it outlines how they're now actually "going all in on the gaming experience on Ubuntu and we’ve started building out a team dedicated to working on just that". Part of that is reducing the need for PPAs and other solutions, and their focus now is on Steam.
The call for testing has now begun on their Steam Snap package which gives you everything you need for Native Linux gaming and for Proton too. It's early days for the Steam Snap so expect issues but they said they will "iterate quickly, and respond to this feedback" on it.
On top of that we can expect more gaming on Ubuntu Linux improvements to come "such as providing easy ways to get more bleeding edge components like Mesa drivers, and even newer kernels and proprietary drivers" — that all sounds great to me.
It's not actually live yet but once it will be, I'll update the post here with instructions they give, which they will also post in the link above. Update: Canonical has now done an additional blog post, going over the instructions. Either install it from the website / Snap Store or via terminal:
snap install steam --beta
With the blog post, Canonical once again reiterated their plan to improve Ubuntu gaming mentioning that "the Ubuntu Desktop team is getting down to work planning for the future, and improving the gaming experience features heavily in our priorities (and hiring plan!)". They go on to mention how "serious gamers" continue using Windows primarily, which we all know as Steam puts Linux at about 1% currently (see our Steam Tracker) but they hope by "improving the gaming experience, and the Steam experience in particular, we can ensure that Ubuntu can become a genuine daily driver for gamers".