I expect Photoshop to contain many highly optimized function routines for photo processing. These routines are optimized by hand and usually use architecture-specific features such as SSE/AVX which is not portable.
Unoptimized (more portable) versions of theses routines exists, but I suspect they will perform well even with M1.
Unoptimized (more portable) versions of theses routines exists, but I suspect they will perform well even with M1.