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.
If Apple truly cared, they would stop blocking older games from being run on newer versions of OSX...