I'm actually starting to be really impressed by the performance of M1 Max, but it took a while to get the Metal port of Myst Online/Plasma to that point. Apple Silicon has tile memory, but no VRAM, and bandwidth to main memory is limited. Tons of work on tweaking shaders to reduce accidental bandwidth usage was required. Time consuming process, which I'm not sure a lot of devs would go through. It's not necessarily incompatible with also supporting discrete GPUs though.
I worry a bit if the Mac has to rely more on stuff like WINE in the future. Apple Silicon is a really different kind of GPU - and translating software meant for traditional discrete GPUs may not always offer the best performance. Also who knows what the future of Rosetta is.
For reference: I started in a place where my desktop Radeon 5700 was consistently beating my M1 Max MacBook Pro. Now, after careful optimization, I have M1 Max running almost twice as fast. I'm optimizing shaders and setting up some memoryless textures, but otherwise not going deep into tile memory mechanics. Not bad!
