Maybe I just have low standards, but honestly its rare that I have problems with Aeromexico. The only (giant) exception is that since the pandemic, their ability to stick to the itinerary they have sold me has gone into the toilet. But once I have a workable itinerary, things generally go as I expect.
I rarely have had bad/rude service. But it is certainly low-energy. What I experience from Delta is a little more attentive, but not remarkably so.