In a 5-year lifecycle that's about 10,000 years of human labour wasted. Yes, I had to quadruple-check this myself.
Does it take 10,000 work-years of effort, per project, to train its developers to write reasonably performant code?
Of course not all of this would translate into actual productivity gains but it doesn't have to.
Unfortunately the number of users and the collective value of their wasted time doesn’t make arguing for efficiency and performance any easier.
I once noticed my name in the Chromium OS credits due to a patch I had submitted to a library that's on every Chromebook. 1 million would be a small number for Chromebooks alone.
The ones that stick out are actively maintained, widely used, and well funded. It doesn't have to be a million active users, but they should be the first to get their act together.