... sort of.

The old model was definitely hell and there is a reason basically no studios supported Linux builds.

These days? Yes, you can go a long way with targeting the SLR. A buddy who does game dev for his day job describes it as "targeting 3/4 of a platform" or being like targeting two generations of the same console. In theory, your middleware handles everything. In practice, you have another platform for your testers to evaluate RCs on and you still find weird corner case weirdness.

But the issue is also... that lets you target the Steam Linux Runtime. What about other storefronts? And the people who tend to care the most about actually making Linux builds are the same ones who aren't fully comfortable with the idea that "SteamOS == Linux" as it were.

So it becomes that discussion of whether the added testing and development burden is actually worth... still not actually being all that great ideologically.

So just AMD and Intel?

With the exception of NVidia, all GPU vendors build their drivers on Mesa, so they are more homogeneous than Windows.

This sentence is written in some form of alien language that looks like human writing but clearly isn't.

Alternately, it may or may not be a particularly playful segment of Alice in Wonderland.