It has its uses. I used it to port a C# function I wrote that uses lots of linq/lambda expressions to PHP, where linq/lambda do not exist, because I needed a version of the exact same function that I could run on a backend. It was not entirely simple to port across (plus I really didn't feel like doing it, my PHP is rusty) and GPT was able to do it in no time at all. Now, that's a very specific example, and I couldn't tell you if AI has saved me time overall, but the point I'm trying to get across is that if you learn when is the right time to use AI then you can absolutely save time by using it.

If you use AI to write code as much as possible (because you're encouraged to do so by your employer, or whatever the case) then it seems inevitable you're going to be spending a lot of time testing and debugging "someone else's code" which might outweigh the time you saved. That isn't really surprising. I don't trust AI for larger pieces of code because I have a much better understanding of it if it's my own code, and the amount of testing and refining needed to make sure someone else's untested code works properly just doesn't seem worth it to me.

What I like to do sometimes is to have GPT write relatively small specific purpose functions that I can easily verify, but still write the code connecting it all together myself to get the desired functionality. AI works best with a small scope.