Not quite. I understand that's a piece but if you've ever tried to solve this problem it's not even close to being as easy as you make it out to be.
1. The stats you cited (k/d) is well within normal variance
2. It's not super common for cheaters to run around spinbotting/blatant wallhacking. I would actually say that's the minority.
3. Depending on the game, that would never happen because MMR just matches you up with people based on your new "skill" i.e. 2 games with 8K/d puts me in harder games and I go back down to something reasonable. Again, most cheaters don't continue to just dominate, those are the minority and get caught easily.