So really, if we're critiquing representation, which is all fair and good, then we should really be looking at engaging further with the content beyond what is on the cover. You should be analysing not just the plot of the story, but the characters and themes and actually engaging with it on a deeper level and working out what the author is trying to say or do with their work.
It's not as simple as going "OMG IT'S ALL PASTELS THEY'RE ALL THE SAME AND SOMETIMES THERE'S A TALL GUY AND A SMALL GUY" because... well... Small guys who fall in love with tall guys is a thing! Boys who all wear pastels and have kpop fashion and date each other is a thing! Couples who do magic or who fight crime is a thing.
I guess what we have to conclude in this thread is: you can only examine mixed messaging if the promotional material of the series does not match with the content of the series OR the creator does not get across their message due to two conflicting structural points in their work being mismatched.