I would also like to know why
As a support champion, he's extremely low tier. He can't fit into any other roles, either.
His slow is a skillshot with a triggering stun. But in effect it's not that great. Compared to Janna with her large AoE tornado, Leona, Namis stun, it's extremely low tier. Even Morgana's snare is favored.
His little healing spell is again, lacking. Even Nami who has a stun and heal do a fair bit better than him. Not to mention he's outclassed by Soraka and Sona if you want just a heal.(Sona has a more potent slow as well, and her ult is extremely top tier.)
His little...travel path thing is gimmicky. Only works over terrain, the enemies can use it thus negating it's use(It provides a speed boost, but considering it's the last spell you'll max a 10% at rank one to 50% at rank five it's.....shitty.). The effectiveness of this spell is lowered extremely because enemies could use it. It's unique in that it's a disengage usable by allies, and it's also unique that it's usable by enemies. Unique doesn't mean good.
And his ultimate...again, it's a gimmick. Sure when you can position perfectly around it it's good, but Sona, Leona, Nami, can do the offensive stunning better.(With actual damage too!). For disengaging, Janna has the extremely better ult.
He's low tier in all regards. Not to mention his gimmick of collecting his passive across the map. Because you know, his whole gimmick is the wandering caretaker or whatever. But nobody does this unless it's an extremely specific strat where your lane partner understands they'll be left alone. Which is still a hindrance through and through.
He's a gimmick champion. Useless in solo queue. His value slightly goes up in teamplay, but only slightly.
Oh I'm not disagreeing with you. Yeah, the 'silhouttes' and general shape of alot of characters are...too similar. It's just that for male characters, the League designers found it 'ok' for them to be monsters, whilst for female characters....they had to be cute and bubbly. IIRC the first female 'monster' was Cassiopiea. Elise and Rek Sai are the only other 2 'monster' like females.
It's just that as it is, there is more variance in the male characters of league than there is female characters, so their logic of 'Bikinis for female characters wouldn't be different enough' is kinda spot on. It's how they as designers, have pidgeonholed themselves over design choices they made years ago.
Like...Draven, Lee, Ez all have a similar body type. Garen, Darius, similar. But then you have Urgot, Mundo, Galio, because it's ok for males to have monster bodies. Meanwhile for females you have....Poppy, Tristana, Lulu, and Annie who have child archetypes, Elise/Shyvana who are transformers, Soraka/Eve/Zyra who are obviously humanoid, Cassi/Rek who are the only monsters.
Shyvana, Elise, Soraka, Eve, Zyra, Riven, Ahri, Lux, Sejuani, Syndra, Sona, etc. all have similar bodies. Slim, nice T&A to go with it, and well, if you strip it down to a bikini extremely similar and boring.
I'm not saying only the females suffer from it, Riots a bit hypocritical in that regard when dealing with the male pool party recipients. But they seem to be trying something different with Zac/Lulu/Rek/Mundo as pool partiers this time around. Draven being the only exception.
Maybe they're learning?
Also you posted Zarya from Overwatch, I'd say Riot has alot to learn from Blizzard. In HotS there's Johanna, an extremely bulky, armor female who's pretty buff. Still attractive, extremely armor-fortified, but she looks great.
