While I agree to a point, learn new heros and get good with them. Then just play them regardless of what your team thinks. It sucks because sometimes you get sad trolls who dont try, but there are more characters than Rein, Ana, Lucio, S76, Roadhog, and Genji.I still play occasionally but this game feels so repetitive. Matches are literally the same team builds vs each other and it comes down to whoever makes the first mistake.
Also, the more characters you know, the easier it is to counter the other team. If you do not know how to counter, you may never reach diamond, let alone master.