As someone that did not cheat (yes, haha, anyone can say this, believe it at your own choice) and had to climb a fair bit and improve at a pace to keep up with my peers... there were more people playing legit than cheating when in the Top 100.

The main reason why it was "this easy" for me was because everyone kept saying "its full of cheaters, you dont have a chance" without trying - people gave up before starting. If a lot more players would've competed, the magnitude of cheating and wintrading would have been much lesser by virtue of them making out a smaller percentage of the total player pool.

Wintrading would also become significantly harder to pull off consistently because of frequency of players interrupting their matchmaking shenanigans.

It's frankly a self-inflicted problem.