Yeah, like I agree with you in the end. I've met way too many liberals and democrat organisers who are genuinely well meaning.

I think that leftists feel that way when these parties sabotage popular, succesful leftists inside them, like Pelosi's attacks on AOC, or the all of Labour on Corbyn and feels very much like they're trying to lose. It's more of a sentiment that is experienced subjectively than is applicable to their intentions.