I think it will happen a bit, but I'm not worried about it.

My ability to write with a pen has suffered enormously now that I do most of my writing on a phone or laptop - but I'm writing way more.

I expect I'll become slower at writing code without an LLM, but the volume of (useful) code I produce will be worth the trade off.

Reading other people's (or llm's) code is one of the best ways of improving your own coding abilities. Lazy people using llms to avoid reading any code is called "vibe coding", and their abilities atrophy no matter who or what wrote the code they refuse to read.