It's hard to look at chat e.g during enemy execute, flashbangs flying everywhere etc.
I remember that a few times, I met some dudes who only typed in chat, no voice and were mad that I didn't notice info on chat during big fight/execute... I mean, c'mon bruh
Ping system is an interesting idea, didn't play valorant yet so dunno how it works there. Played league for a while and ping system was useful but still not as good as (good) voice comms.
Comms maybe are not necessary at "lower level" but I believe that if you want to get better, good voice comms should be a part of your skillset. In fact, if someone is playing at said level, and is not a screaming idiot but tries his best to comm, it always makes me happy.
Another angle is, good voice comms will help you immensely, if you have a bad game. I NEVER flamed or talked shit to player who played badly but tried his best and was good at communicating. That way, they can still be useful to a team. Contrary, when you play badly and comm nothing, sometimes people can dogpile you and flame you nonstop.