I think a lot more people are just upset that Pulsefire Ezreal will be made a lot less special of a skin once PF Caitlyn becomes a thing.
In the past the skins team have said they will keep the Ultimate skin lines unique, but they lied, so I think a lot of people feel a little bit hurt by that.
When it comes to Legendary skins being released, part of the reason why a lot more of the recent Legendaries skins have been to females is for that sole purpose. When the game was first developing there really wasn't that many female characters in the game with truly interesting or decent personality, so there was no point in giving them 1820 skins.
Now that a lot more female champions have been fleshed out and made to be more then fan-service experiments, Riot sees a lot more point in giving them fully fleshed out skins that include new VO.
Had Dark Star Orianna or Project Ashe been made 3 - 4 years ago, not only would have the quality been down, but the designs would have been made a lot more pandery and less interesting.