Thinking about a new Mac, my MPB M1 2020 16 GB can only handle about 8B models and is slow.

Since I looked it up I might as well shared the LLM-related specs:
Memory bandwidth
M4 Pro (Mac Mini): 273GB/s M4 Max (Mac Studio): 410 GB/s

Cores cpu / gpu
M4 pro 14 / 20
M4 Max 16 / 40

Cores & memory bandwidth is of course important, but with the Mini I could have 64 GB ram instead of 36 (within my budget that is fixed for tax reasons).

Feels like the Mini with more memory would be better. What do you think?

There are lots of general-purpose models to use locally, and also coding-specific models.

But are there models specialized in one programming language? My thought was that a model that only needs to handle one language (e.g. Python) could be faster, or be better for a given size.

E.g If I need to code in Rust and is limited to an 8B model to run locally, I was hoping to get better results with a model that is narrower. I don't need it to be able to help with Java.

This approach would of course require switching models, but that's no problem for me.