Try mastering 2 heroes of each role like 2 DPS (maybe u don't need to considering the amount of DPS ppl) 2 defense (maybe u need to just in case) 2 TANKS I reccommend roadhog for lower tiers) 2 supports (maybe like Lucio or zen) anyways this is what I did to get out of bronze hell
I know people who like to start the season hella low and just climb ( they aren't gm's ). sym works super easily for them to get through those elo's. Just ignore the cancer and carry your team.