The other day I was doing some programming without an LSP, and I felt lost without it. I was very familiar with the APIs I was using, but I couldn't remember the method names off the top of my head, so I had to reference docs extensively. I am reliant on LSP-powered tab completions to be productive, and my "memorizing API methods" skill has atrophied. But I'm not worried about this having some kind of impact on my brain health because not having to memorize API methods leaves more room for other things.

It's possible some people offload too much to LLMs but personally, my brain is still doing a lot of work even when I'm "vibecoding".