Summary as given in the post:
1. formal verification is about to become vastly cheaper;
2. AI-generated code needs formal verification so that we can skip human review and still be sure that it works;
3. the precision of formal verification counteracts the imprecise and probabilistic nature of LLMs.
These three things taken together mean formal verification is likely to go mainstream in the foreseeable future. I suspect that soon the limiting factor will not be the technology, but the culture change required for people to realise that formal methods have become viable in practice.