~3 months start to finish and the price of 1 engineer for a year, to rewrite a critical infra codebase that tens of millions of user software relies on. Truly the goalposts keep moving. This kind of project would've have been 10x the effort and price a few years ago.

Yeah, crucially, a lot of such projects never get greenlit.

Claude building stuff means a lot of things that everybody wanted to do, just couldn't allocate the attention or other resources - now get built.