I do, indeed, dislike Ubuntu intensely for a number of reasons.
However, here I cannot fault them. It is time to shift away from 32bit packages for many reasons, not the least of which is that multilib and multiarch repositories have already been unwieldy for some time.
No, the real onus lies at the feet of Valve who have, thus far, steadfastly refused to provide 64 bit libraries and binaries for many titles on Linux even though those 64 bit equivalents exist on Windows for the exact same titles.
However, should Valve continue to shove their head up their ass as hard and far as possible, this isn't the end of anything. What will happen is that someone, quite possibly the distro creators and maintainers themselves, will provide Steam as either a Snap or as a Flatpak. Which one will depend upon which distro you use but you can, generally, use Snap and Flatpak on the same distro without issue.
This allows everything 32 bit that Steam requires (including those 32 bit Nvidia driver libraries) to be packaged up in a nice, self-contained environment that runs without dirtying up the rest of your installation.
I find it ironic that Valve is dragging their feet on this given how much they pushed for 64 bit binaries back in the day and in light of the fact that it's pretty rare for you to find a mainstream 32 bit binary or package on Linux today. This was true even when they started working on SteamOS. 64 bit was the default for most Linux distros back then and should have been Valve's target from the start. I can only surmise that Valve is ignorant, incompetent, or both when it comes to Linux.
"Just take a look around you, what do you see? Pain, suffering, and misery." -Black Sabbath, Killing Yourself to Live.
“Man was born free, and he is everywhere in chains” -Jean-Jacques Rousseau
Purveyor of cute, fuzzy, pink bunny slippers.