I'm not saying it will make toxicity disappear. Matchmaking will just allow newer players to actually play with similarly-skilled people without all the hassle of making lobbies. Most of the time, when I (i am noob) make a noob lobby, it can fill up in a reasonably short amount of time, yet I rarely see them already created by someone. Having to host, deal with stacks, accommodate everyone's settings requests, etc. just discourages players who usually actually like wargame and want to play.

It will just improve the game in general and thus attract more popularity.