Really hard to judge goalie stats out of those leagues. It's obviously a good thing he has good stats, but there are 13 teenagers in the MHL with 0.930+ save % (and that's only goalies who have played 16+ games, so the list doesn't even include Artur because he hasn't played enough).
2020‑2021 MHL Goalie Stats
In the playoffs for example he's 12th in save % among MHL goalies (6th if you want to only look at goalies with 5+ games).
2021 MHL Goalie Playoff Stats
I'm curious to see him in the KHL or AHL in the next few years, because I think that will be more indicative of how he's doing.