This article thinks that most people who say 10x productivity are claiming 10x speedup on end-to-end delivering features. If that's indeed what someone is saying, they're most of the time quite simply wrong (or lying).
But I think some people (like me) aren't claiming that. Of course the end to end product process includes a lot more work than just the pure coding aspect, and indeed none of those other parts are getting a 10x speedup right now.
That said, there are a few cases where this 10x end-to-end is possible. E.g. when working alone, especially on new things but not only - you're skipping a lot of this overhead. That's why smaller teams, even solo teams, are suddenly super interesting - because they are getting a bigger speedup comparatively speaking, and possibly enough of one to be able to rival larger teams.
I think of the Whalphin and it took Sea World era to discover. Who would see that coming?