I fail to see how identifying a working strategy and arguing against a failed strategy is “demoralizing.”
With all respect I am not calling names to your views, even with their lack of apparent progress. DSA won a major election in NYC and is becoming more known. Even then many places don't have a DSA at all, let alone a PSL.
You are at the end of the day ranting about people wanting the general public to vote as left as possible where they are. That is quite divisive.