Current trajectory estimates are more like +2.5C to +3C by 2100 based on existing policy. We've actually managed to move the trajectory downward even though we obviously have a lot to go. Every little bit counts. It is far less binary than this overly simplistic tweet is suggesting
Excessive claims like this end up demotivating people and make them want to give up when we can reduce the damage each time we move our trajectory down by 0.1C
If there were no ranked choice, he still would have won in this case. He won the plurality of the votes on the first round (unexpectedly and a massive over performance of the polls)
Granted ranked choice may have made more people feel safer to consider him in the first place, but still worth noting here