The implication is that the gatekeeping has become marketing dollars, when it used to be skill at making a fun game. I don't think we're in a better situation today.

There are fun games that succeed without marketing, e.g. Balatro, and there are bad games that fail despite it, e.g. Highguard.

The reason that “skill at making a fun game” doesn’t guarantee success is because there are so many fun games. Much less, if at all, because there is so many slop.