Ars Technica:

Valve says Apple has denied approval for the iOS version of its Steam Link app—which allows users to stream PC games from a computer on the same home network—after Apple initially approved the app earlier this month.

“On Monday, May 7, Apple approved the Steam Link app for release,” Valve said in a statement sent to Ars. “On Wednesday, May 9, Valve released news of the app. The following morning, Apple revoked its approval citing business conflicts with app guidelines that had allegedly not been realized by the original review team."

Not cool, Apple.

I can’t see, at all, what this interferes with, any differently from the multitude of streaming services for TV shows and movies which would be in conflict with the iTunes Store.

This is just a streaming option, period. Get your head out of your ass, Cupertino.