"The Democrats"? No ... there are many, many officeholders nationwide belonging to the Democratic party. AOC and allies don't speak for all of them. You've overgeneralized.
When AOC says something ... that's not "The Democratic Party" or "Democrats" saying something. Same for Biden, Obama, Pelosi, or any individual or group of individuals you care to name (e.g. "The Squad"). Same goes for Democratic voices on social media, traditional media, in the blogosphere, etc.
Exact same goes for the GOP, of course. Trump does not speak for the whole party. Neither does Ted Cruz, Chris Christie, Kasich, Giuliani, etc. Similarly, Tucker Carlson, Hannity, Glenn Beck, etc. don't speak for all conservatives.