This happens so often and it boggles my mind.
If you are going ham like 8/0 and someone else on your team is doing poorly, maybe 0/3 or worse. Don't immediately accuse them of feeding and flame them out of the game. If you are better than your opponent and crushing them, can you not figure out that the enemy might also have someone who's better than their opponent.
I played in bronze to help my friend get out a while back and every game they would flame their adc for being bad, complain about how god awful their botlane is and the like but never once did someone admit that I was better than theirs
Nobody is ever willing to admit that someone on the enemy team is just better, it's always "We could have won but we got the trash bot that fed you. GG" or "You suck dick but our adc just trolled all game so now u win"
It's such a toxic environment and it must ruin the game for so many people.