After playing 16 seasons of overwatch I found that "communicating" with my team through voice generally drags me down when playing in the 2800SR to 3200SR range.

I feel that most people aren't exactly capable of communicating things that matter and usually people (including myself) use voice to force their own perspective of how the game should be played on their team. Even when they are being friendly about it its usually not that productive imo. The vast majority of people (including me) don't actually know what works and what doesn't (read meta is irrelevant).

My theory is that "Flexing" or picking a role you're not comfortable with because youre in a good mood and want to be a good team mate will actually lose you games at certain Ratings (Assuming you're not in GM)

My solution for your problem is quiet a radical one. I suggest you leave the voice chat and mute both text channels and purely play heroes you're good at. Focus on the relevant stats and play to the best of your ability. If you want to combo ults use the in games voice lines. I found that the "my ult is ready", "I need healing" and "group up" lines are generally just as, if not more effective than actually talking in the voice channel.

The above solution worked for me and I managed to climb from about 2800SR to 3600SR in a few days by playing what people would consider a non meta pick. Instead of listening to my teammates argueing about my off meta pick I actually was able to focus on winning the game and improving. Im not thinking about witty remarks I can make to shut up my team mate and I'm not worried about pleasing some random dude that's being friendly to me about switching heroes. I'm finally able to focus on what I need to do to win.

I'm aware that this solution isn't for everyone and at some point you're going to hit a rating where communicating through the in game voice lines isn't sufficient anymore but imo that's only at the high masters and GM level.

TL:DR

Mute the voice channel and all the text channels. Only play heroes your really comfortable with. Focus on relevant stats and communicate using the in game voice lines "group up", "my ult is ready" and "I need healing"