This has been true for a long, long time, back to Hofstadter's book "The Paranoid Style in American Politics" in 1964.
Blue bloods were always threatened by it of course, but they used to be split between liberals and northeastern Republicans.
I'd say using populist as an uncontroversial shorthand for bad is a pretty big change for a movement calling itself 'left'.
(This is to say nothing about Orban's merits or lack thereof, just noting the terminology)