It's a a few difficult days for Linux games, but the battle is over. In response to Canonical's plans for 32-bit compatibility libraries, Valve announced that it would support "probably" Ubuntu 19.10 and 20.04 LTS.
After Canonical declaration after "the huge amount of comments this weekend" Statement of Valve has been posted by developer Pierre-Loup on the June 26 Steam forums. He explains the situation as a whole:
In response to concerns voiced by ourselves and the wider community, the Ubuntu project recently discussed a more conservative approach in which a selection of 32-bit libraries would still be available on the host system, via at least 20.04 LTS. We are still not enthusiastic about deleting an existing feature, but such a modification of the plan is extremely welcome … Based on the information we have to date on this new approach, it seems likely that we can continue to function officially. support Steam on Ubuntu.
However, not all things are optimistic for Ubuntu. Valve currently recommends Ubuntu to Linux players as the officially privileged Linux distribution officially supported. This may change in the future:
The Linux landscape has changed dramatically since the release of the original version of Steam for Linux, and as a result, we are rethinking how we want to approach distribution support in the future. There are several distributions on the market that offer outstanding desktop experience, such as Arch Linux, Manjaro, Pop! _OS, Fedora and many others. We will work more closely with many other distribution managers in the future …
That being said, we have nothing specific to announce at the moment regarding the distributions that will be supported in the future; wait for more news on this front in the coming months.
Although Valve is not enthusiastic about Ubuntu's likely plan to cancel compatibility with legacy 32-bit software after Ubuntu 20.04 LTS, there is no immediate change. Linux players can continue to use future versions of Ubuntu to run the Steam game library. The community has been heard.
The full statements of Canonical and Valve are worth reading if you are interested in this topic. Thanks to OMG! Ubuntu to spot that.