Game developers don’t use OpenGL and 32/64-bit is irrelevant. They use cross-platform engines.
You’re missing the point. The reason both being divested was significant was it showed game devs that Apple doesn’t support any backwards compatibility at all and expects everyone to move along with them. There are a lot of legacy titles that are 32 bit, including Valve’s entire catalog of games, no longer playable because there’s no 32 bit app compatibility layer like Windows 11 has