If you're not longer the "hard carry" in your current ELO it means you don't possess the skills to do so. This means you need to improve your gameplay to continue doing so. Just watch your VODs back, compare it to higher rated players, watch some guides and learn positioning, improve your accuracy in training grounds / vs bots and possibly look at your picks.

It's really not the systems fault you get hard stuck because of bad team mates and uneven teams, that happens in EVERY competitive game out there, including GM/Top500 matches in Overwatch.

I play at an average 4200-4400 SR games most nights in the week when I get time to play and I can guarantee you at least 1/5 matches have a troll pick who doesn't join comms while insta-locking Torb/Sym regardless of the map, and you probably win 50% of the matches with this pick on your team. Just ignore their pick, focus on your own gameplay and try your best to win.

You're actually at the rank where turning off voice/text chat and completely focusing on your own gameplay is actually the correct thing to do. Yes it's a team game, but VERY LITTLE of what is said at that ELO is useful information and more often than not just leads to a team abusing each other over chat and increases the chances of somebody throwing the game because they're upset.

Just mute people, record your gameplay and focus entirely on improving your individual skill.