They’re no where near left compared with other countries: the US Democrats are centre-right.
Bernie Sanders is the only one I know of who’s actually left-wing.
This is because US politics’ overton window has shifted right since the 1980s. And will likely remain that way for the foreseeable future.
The democrats actually trend left of major labor and social democratic parties around the world but why let actual policy comparison get in the way of the narrative?
Why make original comments when you can just spam the same garbage over and over?
I could ask “BeRnIe WoUlDa BeEn A rIgHt WiNgEr In YuRoP” spammers the same thing, and with far more counts to answer for.