Curiously, Wikipedia calls the Social Gospel "a social movement within Protestantism," though my former Catholic priest (we have a new one) was also known for preaching a social gospel.
The social gospel checks off every box of socialism, so I wouldnt discount its roots in socialism or self-salvation.
https://en.m.wikipedia.org/wiki/Social_Gospel
“The Social Gospel is not about salvation.”
“Social Gospel”. That’s a new one on me. Sounds awfully PC.