we also found the same as the OP, It's good for simple problems or boilerplate, not great for more complex problems.
It is a value add, but I'd put it closer to 0.5% if that. Over, say, 8 hours of coding time, it might save me a couple of minutes total.
Which, from a company expense perspective is still worth it, but an order of magnitude less than your anecdote.
It's very hard for me to envision how copilot could save someone that kind of time.
I am an experienced programmer, but sometimes I'll have a clear intention in my head of what I want to do, and the knowledge/experience of what code would accomplish that thing, and I still back away from it and start looking at something else, whether work, social media, whatever. Writing this, I know it might sound ridiculous or lazy, but it's true.
Copilot bridges this gap, often miraculously. The gap between thought and code is shortened, and the windows of time where I might lose focus seem to be drastically shortened.
For me, the key is that I do know how to write most of the code that Copilot writes for me, I'm just not good at actually writing it, or at least doing so in a sustained, consistent way.
The novelty has definitely worn off for me, at least.