> in 2026, it'll be 11 developers writing it over 11 years.

Perhaps too, a tool that's been around and in active maintenance for 11 years has been wildly successful.

I wouldn't say "wildly". I would say that it's critical enough to the company's workings that they devote enough resources to it to keep it going, but not enough resources to consider re-writing it or re-factoring it to be easier to work on.