I think everyone agree with you, especially Bep who already stated clearly that he has some good ideas about working on those area, and some WIP.
But the point for this main post is : What is the use case for having a full pagination work for 750.000 pages.
Where is the human who will search something this way ?
So even if 750.000 pages with pagination will build under 10sec, I suspect this doesn’t makes sense from a design/UI/user point of view