Wait, we measure her ideology and party loyalty based only on her endorsements of challengers to incumbents who are black? That's the only measure we need? She endorses Democratic challengers for Republican seats. She endorses Democratic challengers for Open seats...but those aren't measures of her support for Democrats? Or maybe...just MAYBE...you're cherry picking breh.
Romney endorsing Biden would be Romney endorsing a member of the opposing party to his own. Do you have ANY examples of AOC endorsing a Republican challenger at all? Let alone endorsing a Republican challenger to an black representative? But while we're discussing party loyalty, I did find a disloyal Democrat who bolstered a Republican campaign in recent history...
Joe Biden’s Paid Speech Buoyed the G.O.P. in Midwest Battleground
Yes, cherry picking blatantly. Also, I'm not sure if bad faith or just really bad at constructing analogies, but you appeared to attempt to paint AOC endorsing progressives to endorsing Republicans. That's obviously not happening although there are some examples of Biden being way to friendly to Republican campaigns (fitting your analogy far better than any of AOC's endorsements).