The problem with Xayah
Throughout playing League I main ADC, I can't say I'm a good ADC at all. As I played my role I grew an attachment to Xayah, shes a great champion and not really played much at all. In fact she has a play rate of 3.32 %, and a ban rate of 0.08 %. You don't see her played in games that much anymore despite being an amazing champion, however through out the years of her release better marksman have been released to brutalize this champion.
Xayah is not a popular pick anymore and her win rate has dropped from the regular 52 % mid 2019, to a 47.2 % in 2020. Almost every marksman counters her, many jungle can out play her. She has a lot of potential mid and late game, even early game, but it's all drowned out. Shes meant for team fighting, but when almost everyone has a dash, when almost everyone can out heal you, almost everyone is now a tank, it's not mattering for her. She has been taken out of any meta play, and isn't played often anymore. Her ult cooldown is 130 seconds at it's 3rd level, don't get me wrong it's a great ult. She becomes untargetable, she lays out 5 feathers, and she can move while using it. However to use it fully you have to use your E, that's two abilities for her ult to be actually used, other then that you're using it to dodge. All of this while you still can targeted by ignite while using something "untargetable". Compare this to other champions, Jinx has an ult that also can be used in close team fights, yet it only uses 1 ability, and has a 60 second cooldown at 3 levels. Xayahs ult can end up doing 465 damage without AD scaling. However her AD scales 100 % for a maximum 200 damage ult, and 60 % per feather of 95 after her E is maxed. Still using our example Jinx, she does 450 physical damage, with a scaling of 150 % AD and still has an AP scaling. A lot of champions ults are just plain better, Lux's can get to a 40 second cooldown, with a magic damage of 500 with 100 % ap scaling, Caitlyn with a 750 damage ult with 200 % AD scaling that can go up to a 60 second cooldown. I can list champion after champion with a better kit then poor Xayah's just by a problem I personally see with her ult. If you want to go with the ults I listed can be dodged easily, so can Xayahs, she only has a range of 1100, and as I said every champion is now getting a dodge in their kit or a movement speed or health or something.
There are many champions out there who have not been showed love, and personally I think Xayah could use something to help her through the meta. Xayah isn't a mobile champion, she struggles against long range champions and very aggressive champions. Her deadly plumage got nerfed in 9.24 and I don't disagree with this nerf but it also murdered her play after the crit weapon changes. Xayah has a low auto attack range of 525, something she needs for her feather set up, the only ADC's that stay there with her are Jinx and Kai'sa. As of now Kai'sa is getting buffed, and Jinx is a really strong champion to play already. Lucian has 500 along with Sivr, but Lucian has a double dash and Sivr has a passive and ult that gives her movement speed to catch up. Xayah's W gives her movement speed if you hit someone with it, giving her a lot of pressure, but at the same time shes sadly countered either way even after her E by dashes or tanks, something she has troubles catching up with. I can go on and on with her and what's making her such a weak champion nowadays, and some of it seems like gibberish, but these are my thoughts. There are probably countless arguments out there, and I do know she's 100 % a champion who relies on set up. I personally want her to come back and played more, but she needs some love, she needs something to help her back on her feet in my personal opinion.