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
Note that this article is not about the US