My bottleneck is how efficiently or completely I can keep the problem I'm working on in my head, not how quickly I can look up a function name or variable or type out the actual code. Really, only the latter is helped along by autocomplete. I find myself with that feeling of my mind slowing down more and more as I get older. When I actually get around to writing the code itself, the problem is mostly solved from my perspective, I'm just dumping out of my head into the editor, that part is easy. Until an autocomplete is wired up with an LLM and LSP which knows exactly how I think and approach problems and remember the codebase, it'll be mostly useless for me. So I don't bother.