Perhaps read the rest of the sentence as it continues with "any more than I had before using them [AI/LLM]". We're all only using these tools for ~2 years at most, so if some people are noticing degradation, I am saying that I haven't yet. And so when you say "That you don't notice it doesn't mean it isn't happening.", I agree. But that's off topic, because we're discussing what we've noticed, not what we haven't noticed.
…said every drunk person ever.
That you don't notice it doesn't mean it isn't happening. By the time you notice it, it's too late.
That's why elderly people who are worried about their brains play chess and do puzzles like mad.