The bigger problem with aggregates like MetaCritic are that, there's almost no consistency in metric standards carried between games, even within the same genre. It's a crapshoot if a publication puts the person who enjoys open-world RPGs on an open-world RPG for review, or if they put them on a visual novel game to review instead. That alone can skew the score for that game from that publication, which can skew the average.
Then there's the fact that reviews are weighed based on the website, so not all outlets have the same weight into the aggregate as others. An IGN review will have more weight into the overall aggregate average than one from, say, WePlayGames! or some other website you've never heard of. Problem there is that it's a system open for being gamed, and it's not like most journalists are paragons of journalistic integrity and virtue in the industry as-is. In fact, we've had instances where some reviewers clearly did reviews on games to purposely run contrary to popular opinion simply to stand out and get clicks, not because those reviewers GENUINELY believed what they thought to score the game the way they did.
Probably the most egregious recent example of this was Stevivor, not just with their HFW review but also their reviews for Demon's Souls Remake AND Bloodborne scoring well below the MC average while somehow, all of their other Soulsborne reviews were in line with the MC average or even slightly above it. And when the only common link between those and the two which scored well below is that the latter just happened to be exclusive to specific consoles from a singular platform holder....eventually that tendency is going to be spotted and you're going to be held accountable, hence them getting blacklisted.
I definitely think there's a way to codify the review process industry-wide among the different websites and aggregates like MetaCritic, and with the platform holders as well, but it'll require a lot of work.
I think they meant more for AAA games, where the review scores are a bit more a factor. A big AAA game netting below 85 on MC will probably be hampered in total sales potential compared to games that clearly get above that mark.
There's a tendency, unfortunate or not, where a lot of hardcore/core gamers consider any AAA game getting below an 85 (or in some cases, below a 90) a "failure". It's BS, but that's the environment these days.