The problem is, the low hanging fruit, the stuff it's good at, is 90% of all software. Maybe more.
And it's getting better at the other 10% too. Two years ago ChatGPT struggled to help me with race conditions in a C++ LD_PRELOAD library. It was a side project so I dropped it. Last week Codex churned away for 10 minutes and gave me a working version with tests.
I think that typescript is a language uniquely suited to LLMs though:
Contrast that with C/C++: I'm not sure I agree that typescript is "90% of all software". I think it's 90% of what people on hacker news use. I think devs in different domains always overestimate the importance of their specific domain and underestimate the importance of other domains.