Wouldn't really want to do heavy computational work on any laptop. Thermal throttling will gut your performance. Laptops just don't have the cooling necessary to have it any other way.
I think it’s just a question of time until Apple offers hardware support for BFLOAT and other formats on the GPU and AMX (they already have BFLOAT16 in the CPU), at which point their ML performance will improve dramatically.
I suspect this will gradually change, perhaps especially now a lot of effort has been made to bring tooling such as PyTorch over to Apple silicon.
> on CPU instead of GPU
But Apple isn't doing it on CPU.
You are thinking in terms of x86 discrete components.
Apple Silicon is a fully integrated architecture including unified memory. That's what makes it so efficient.