I don’t play DOTA2 but that’s some seriously great live service management. Smurfing in Overwatch2 drove me nuts (I’ve even given up playing the game). Constant leavers, toxic behavior, and no repercussions.
Tracking smurf accounts back to their main (likely by reviewing IPs as one account logs out and another logs in) is a powerful way to stamp out this behavior and deter people from smurfing in F2P games where having multiple accounts doesn’t cost a cent.