There's not much to say it really affects the sales of that particular game. I think it helps more so in the way that if you bought a game, and everyone thumbs upped it, you're more likely to not hate it as much and more likely to pay attention to the next game like it or in that series.
Battlefront II reviewed at a high of 68 and low of 65 on the Critic portion of Metacritic, the user reviews are 1.3, 1.4. and 1.4. The game sold 9 million copies in three months and EA was expecting 10. That was a huge controversy. That wasn't just gamers being mad about something. That was a game that a lot of very casual folk buy because they love Star Wars. Mass Effect Andromeda got slammed pretty hard for a game of its popularity too and still according to EA, sold well and had great player engagement (whatever the fuck that means). TLOU 2 leaks also barely influenced preorders for the game.
The point is, sure some big review might influence people that are more involved with games on a daily basis even when they aren't playing them but a bad review of a game is only going to deter those who are watching reviews as they come and discussing games fairly often when they aren't playing them. I know plenty of people that are just aren't involved in talking about games. They don't give a fuck what reviews say. The game is exposed to them via ad or word of mouth (usually the best influence a review has on sales is word of mouth it seems) and they normally decide whether or not they're interested and wanting to buy it then and there. TLOU 2 leaks only affected people who are on forums or Discords talking about game news or that have that kinda news in their social media feeds. Plenty of people I know that buy new games don't have time for that. They work overtime, they have a family, they have a house to tend to, and their free time relating to video games is playing them seeing as they might have 4-8 hours a week to play games. They don't want to spend 4 of their 8 hours a week they get to play games on people talking about games and arguing about them. That's a huge portion of sales. As are kids, who usually are none the wiser to bad or good reviews. I didn't read reviews as a kid. I had friends tell me about games. I read the back of boxes. These kids see super cool space man and they'll buy the next Mass Effect or at least ask for it at Christmas.
If a game getting good reviews really affects sales, it's not enough that I could imagine Sony paying all these outlets to give it a 94+. I just can't see it knowing what I've already seen between scores and sales. It just doesn't seem that logical to spend a lot of money on reviews to have it influence a few people. Most people, in my opinion, that are heavily involved with the current happenings of game news and game design and so on are also way more opinionated than your average buyer. The average buyer just needs a bit of excitement, some good looking graphics and they're more than likely sold. They don't hold games under a critical lens. I've pissed a fair few people off in real life because they wanted to know my opinion on Fallout 4 and other games and I'm just like yeah man they fucking suck. And their opinion? It's not New Vegas but it's damn near close in how good it is.
I'm sure that even something like Fallout 76 couldn't have been saved by 90+ review scores. People were immediately upset when they saw that, the general public largely didn't care for such a thing.
EDIT: Looked up a study (haven't fully read it yet) done on some really unknown games and the user review and critic review biasing it had on people. Seems that despite the type of review (critic or user), it definitely had an impact on whether or not a player liked their experience with a game. Mostly that players that read negative reviews showed a larger bias shift than those who read positive ones. Example: Read review that said 50/100 and gave the game a 25/100 vs. Read review that said 80/100 and gave the game a 83/100. Something like that. But that also comes into question of whether or not reading a review or review score would affect the decision of purchase, how many purchasers read the reviews, do the final scores matter more than the text of the review or vice versa, how does controversy play a part, etc.
