I question the framing of 'radical' from the jump. Progressives are only labeled that bec Overton Window has been dragged so far to the right that anything left of center-right looks "radical" to rw extremists. Let's not forget today's progressives advocate same things as the 1956 GOP platform.
The framing of these Democratic primaries by many news orgs is "how did the party let these radicals take over?" instead of "what is going on in the country and the world that leads so many people to vote this way?"