Political jargon is confusing. But I think this case they refer to economical right-wing, who typically support deregulation of market.
I think calling “modern left” “liberal” is kind of confusing, since most modern left support social freedom and economical control, which is not really “liberal”. But that is the terms we stuck with.
I don’t think that is a good strategy to convince people to leave. Also it adds strains to the Lemmy instances.