LLMs might hit a wall. Any technology could hit a wall. ChatGPT could be the next Segway. But, like the Segway, LLMs are useful now. I think the impact of "stuff like ChatGPT" on software engineering will equal the impact of the compiler in that eventually no one will consider writing software without a "stuff like ChatGPT" in the tool chain, in the same way that no one works without a compiler now. LLMs are useful now and they've only existed for a few years.

But that's just my opinion and no one knows the future. If you read papers on arxiv.org, progress is being made. Papers are being written, low-hanging fruit consumed. So we're going to try because PhDs are there for the taking on the academic side, and generational wealth is there for the taking on the business side.

E. F. Codd invented the relational database and won the Turing Award. Larry Ellison founded Oracle to sell relational databases and that worked out well for him, too.

There's plenty of motivation to go around.