I really don’t understand why Warren keeps being put in the company of Bernie or AOC.

For the same reason Corporate Dems kept screaming "Biden is the most progressive candidate since FDR!" at any left-liberal who would give them the time of day. She's not a serious politician. She's a fence post. This is how far the party is allowed to go and absolutely no further.

You put Warren in with Bernie and AOC today. Then, when we get another Hillary or a Buttigieg or whatever on the ticket in 2028, you can tell progressives "See? Warren is being reasonable and joining with the very popular center of the party. They have progressive cred. Idk wtf Bernie and AOC are on anymore. They've clearly gone off the deep end. Besides, Bernie is a misogynist and I think I heard AOC is part Chinese. And don't even think about voting for the Green Party. They're all a bunch of KGB-infiltrated Russians."