I do think there is a level where there is to large of a port no matter the flow rate. Where that is, is a great question that I’m sure is super dependent on the combo of the build and what it is designed for. There is no clear answer to this unless your working on your engine, which still, require testing to actually know.
Freiburger of Engine Masters tried to find this out on a stroker 408 Ford and a tiny 218@050 cam. He had 3 differently ported levels of the same head and the big head made the same lower as the smaller head while the mid size made more power everywhere. This is a clue in this game.
Another thing I have said in the past is when your getting a ported head, look at what’s out there. Compare compare compare everything you can about the heads. And then look at your cam lift. If you’d only lifting to.500, then compare the heads flow rates to .500 because everything else there after dose t help in wing power. It’s not being used.
And as Greg said, price! Also consider the rocker gear as part of the total package price.
