Voice chat is necessary for immersion. Let me explain why cause that statement is very vague.
In terms of joining a random multiplayer match, a good option would be to have eveyone muted by default, and in the case you found a good teamplayer or someone who is doing something wrong or in general want to communicate with someone, you could send a "voice session invitation ", where if the other player accepts you both join a voip channel in-game.
Why do you want to talk to someone???
Personally, I don't want to play with bots. And that's exactly how it feels when playing an online game and don't get any immediate feedback. Half the time I feel like im in a multiplayer session with kids in an internet cafe in Zimbabwe. Sure there are many immature players (including myself) but with VoIP, the chances of joining clans, meeting better players and more memorable moments in gaming increase.
Why not just join discord or something similar?
Simple, it's too much of a hassle, and there's no way you can convince randoms to join your server or theirs. Also, third party apps usually take up allot of ram and cripple gameplay performance.
Furthermore, if this mechanic can be implemented with in-game proximity features (Mumble for Project Reality BF2) it certainly can make mods like PW so lively and fun to play (join a current warband PW server and try halting someone, trust me you will feel dead inside just like the server cause noone plays anymore something in 2020 without microphone functionality)