Like other commenters already said, there are numerous ways they could have avoided/reduced the $500k/yr cost pre LLM, including simply paying someone to do port the code.
So I don't see there is any point in the article.
The point of the article is that that was his way to do it. To show that it is possible to save money with AI rewrites.
The point of the article is that that was his way to do it. To show that it is possible to save money with AI rewrites.