I have an M1 Max MacBook Pro as well, running macOS Ventura. SketchUp still appears to running ok. I used an app called GLView, and it tells me that OpenGL 4.1 is still available to apps. I don’t know if there is a translation layer to then really do things with Metal 3, but however it works, SketchUp is running faster than my work Intel Mac
I found this discussion about switching to Metal:
It wanders off a bit, talking about how few Macs there are, but that doesn’t matter really. Close to 100% of Mac users would be happy to see SketchUp using Metal. You could add some comments to that topic.