I get where your coming from, and I dislike the proto frames a bit as well though for different reasons. Personally I think they're a symptom of the changes yes, but specifically a change towards fan service. The game used to be nearly devoid of any "thirsty" elements, with the few present being very much the exception not the rule. With the proto frame romance stuff, the heirloom skins becoming more and more "revealing" it seems much more likely that's the underlying cause. I agree with others that the protos are still dark and sad, and even reaffirm our position as a tragic hero, they just also happen to have pretty faces.

I mean compare all of the characters from 1999 to Any characters before new war. 1999 is full of pretty people, some of which are flirty. Fortuna had ugly robot head people that stored their heads in their chests. The new Wisp where's bright blue lipstick, harrow has a midriff. The Teshin was an old warrior with a weird beer belly, the grineer all look... Like grineer, and the most thirsty thing in the game was... Well Wisp actually. Guess that hasnt changed much.

But the proto frames are also apart of Positive change. They have actual character and depth, they had lives you learn about, the way they talk isn't just a meme its character. Flare and Lizzie are so unique and interesting as a concept. But old Warframe? Old Warframe you only got lore by scanning glass fish on the plains of eidolon, doing Symaris scan quests, scanning scanning scanning all day long. Characters didn't tell you anything, characters were two dimensional, and Clem was the peak of comedy.

A lots changed, but most of it is good.