Do you PR or raise an issue to every package you use? You can still use 2500 different packages for free. This seems like a good example how it would work well.
My point is that you are taking their point too literally.
Also, the business model is paying a subscription for the right to submit a pull request. Sure, you could wait until you are about to make the PR to buy the subscription, but that's a pain of its own.
Their point here is that this isn't a scalable business model. That's the assertion that started this whole comment thread.