Rosetta 2 can't go away until Apple is ready to also retire Game Porting Toolkit. At most, they might drop support for running regular x86 macOS applications while keeping it around for Linux VMs and Windows applications, but that would be pretty weird.
In principle, the Linux Rosetta binaries should remain usable well into the future. Even if Apple discontinues support for Rosetta in their VMs, there's very little (beyond a simple, easily removed runtime check) preventing them from being used standalone.
AFAIK Linux Rosetta does not work standalone but uses some channels to exchange x86 and arm binary code between Linux guest and macOS host. Actual translation happens in the macOS.
I don't understand why Apple even bothers these days, I wouldn't be surprised if Apple's gaming market is a quarter of what the Linux gaming market currently is (thanks to Valve and their work on proton and by extension wine)...
Because people want to use their fancy new hardware to play games? Linux market share wouldnt be increasing so fast if Valve didn’t do the work so why shouldn’t Apple do the same?
They don't really block games though. It's more like they don't want to maintain the roads the games need to run on.
Transitioning to ARM wasn't possible if they had to support 2 x86 ABI's and an extra ARM 32 bits ABI. Throw in another migration and you have an untestable number of legacy combinations.
