Wasn’t Zephyr Teachout one? She was an up and comming progressive that said something (can’t remember what) “impolite” about Biden (i think) and Bernie distanced himself from her and applogized for what she said.

I think this opinion piece is it… Zephyr Teachout’s opinion piece in the Guardian, “‘Middle Class’ Joe Biden has a Corruption Problem…”

Washington Post opinion piece about the opinion piece and Bernie’s response, by Paul Waldman… from the first paragraph…

“Bernie Sanders did a strange thing the other day: He apologized to Joe Biden for an op-ed written not by him or his campaign but by a supporter, law professor and anti-corruption crusader Zephyr Teachout.”

There was also some people who made pretty good videos independently supporting Sanders, who were brought into his campaign and then dumped when the “cancel culture kids” found something they didn’t like about the content creators.