I can appreciate that many people have no real concept of cost at scale, but Apple currently handles 100,000 submissions per week[0], which doesn't happen for free.
The question isn't whether Apple can afford to run an App Store. They clearly can. In fact, they currently profit from the operation, and are proud of the fact, which I think is a huge part of the problem.
What I said was that Apple initially ran the App Store at a loss and hoped to break even. That was true in 2008 when the App Store first opened, and it remained true during Steve Jobs' life, so at least 2011.
Some time after that, they stopped operating at break-even, and started profiting from it. I'm not sure when exactly that was.
[0] https://appleinsider.com/articles/20/09/24/app-store-rejecte...