I think stats don't reflect how well the player played during a game (ignore much lower or much higher ratings which are obvious).
Imagine an instance where player is getting a kill of solo anchor holding a site potentially increasing chances of winning the round and opp team going on an eco next round and someone dying in 2v1 while double peeking but instatly getting traded. These both scenarios are crucial in winning the round. However, person in first instance gets lower rating for that round than person just trading in post plants or in second instance person getting much less rating despite playing perfectly. There are many other instances which contribute to winning the match and getting lower rating also many where kills matter less and getting higher rating than the one getting impact kills.
Also, the midrounding, micro level comms in situations by a player, vibes, etc are not taken in account when deciding how impactful was the player during game.
Although, stats are good for getting rough idea, but player should not be completely judged solely based on stats.