It already ships with its own libraries, so it may not even be affected. If it is, then a new snap is going to be created for it. Right now you can also use flatpak: https://flathub.org/apps/details/com.valvesoftware.Steam

Which libraries? I recall having to pull in a whole 32-bit system on Arch Linux to install Steam’s binary package.

Arch gives you the option to use the system libraries or the built in one using steam-runtime or the steam-native binaries. But the package needs to install the 32 bit libraries to give you the option.

I think Valve were already forced to go 64 bit on MacOS. At a certain point I have to imagine that releasing a 64-bit client will be the path of least resistance.

For one thing, new games on Linux should no longer be targeting a platform that should have been phased out before Steam even launched on the OS.

And people will no longer need a duplicate set of libraries on their machines, all the way down to the gfx drivers. New software, and old stuff with 64-bit support, should have a lot less compatibility issues.

Valve will continue to distribute their own libraries because this kind of thing is why Linux is a nightmare.

They need to upgrade anyway due to MacOS changes that are coming