Just lost about 30 sr from a match and I’m almost 100% sure it’s due to the poor number my winston performance produced. I swapped to him to try and get back to defend point A on blizzard world faster than I could get there on Reinhardt. But I didn’t make it back in time and after I died twice trying to stall the payload I swapped back to Reinhardt to better hold position. Was on winston for maybe a minute and a half so my numbers were abysmal compared to someone or even myself if I had played the whole match with him. Can we please get this SR system to better reflect actual skill and not luck of the draw with wins and sticking to just one character?
Technically the performance base match metric accounts for a small portion of your SR adjustment, other factors include the comparison of average SR between both teams, how frequently you play, and how close to either end of the SR range you play at.