For me - I'm 43, and used to be an extremely productive Java/Swing developer after 15 years of experience, and I knew all my tools inside and out. But I no longer work at that company (which doesn't exist any more), and it takes me a lot longer to learn how to be effective with the new tools I'm using simply because I haven't had a decade to learn the ins and outs of the new environments I'm working with.

So AI saves me immense amounts of time figuring out how to write proper syntax, remembering the ins and outs of unit testing frameworks, etc. If I stick around for a year or three I'm sure I'll get much much faster and learn these tools better.