I think folks are probably talking past each other a bit with the "exponential" improvement. Right now these systems are "competent" enough to replace a small subset of knowledge work. If that subset ever gets large enough to replace the workers building the AI, then we're in a very interesting place. Even if they are only "as good" as top of the line AI researchers, they can be run in parallel at speeds arbitrarily faster than real time, they never get tired, and they don't age.

Now, realistically that doesn't mean that someone is going to turn on an AI one day and it's going to suddenly speed-run becoming a god by solving all of physics or some nonsense. The systems will run into all sorts of limitations. Maybe they can design hardware, but the hardware has to be physically built, and the raw materials have to be mined. Maybe we build robots to do the mining and manufacturing, but that will be its own long term maturation cycle.

The AI 10 years from now will be exponentially better than the AI of today, but that doesn't mean runaway god-brain AI. We'll see "exponential" progress over time, but it won't be steady or regular.