Progressives love her for one. And how is she not?
Bannon and Spencer both like her (she refused to condemn the former, so no surprises there). She was one of the only Democrats under serious consideration for a job in the Trump administration, next to Joe Manchin. She used taxpayer money to go on a trip to visit Assad and raised doubts about his attacks on civilians. Anyone who didn't like Hillary for being a flip flopper should hate Gabbard considering her change in stance on abortion and gay rights (as for the latter, the LGBT caucus endorsed her primary opponent for obvious reasons). Don't insult progressives by claiming they generally love someone like Gabbard.
If the only thing she had done differently in her career was endorse Hillary, you wouldn't be going out of your way to defend her.