Singed - too much effort for too little payoff
He's honestly unplayable in lane at this point. Anyone with heals, range, mobility, or the ability to build an early spectre's out trades him every time. Anyone with healing outsustains him because it takes a lot of mana to fling. Anyone with range just pokes him, and he has no way trade with them outside of an all in. Champs with mobility can either avoid him or stick to him. Their choice. Spectre's trivializes laning against singed, because its mechanics naturally fuck his Q on top of straight up reducing the damage with mr. Hex drinker does the same.
His auto attack animation is awful. Until he get points in q, he will be behind in farm. He will be behind in farm all lane because he's so easy to zone off. Singed is gold dependent. He needs to build a lot of movespeed because his kit doesn't provide enough on its own, and that stat is actually very hard to come by.
Singed has low damage, minimal mobility, and no way to deal with most lane matchups that aren't jax. Playing him is like trying build an airplane out of a rubber band and a paperclip while the fiora you're laning against has brand new jet. I used to be able to brush off the occasional riven, and I could handle being down until I got my ult, but new champs are so strong and trade so well that he cannot compete without a lucky fling into a minion wave or tower. If it weren't bad enough, his early mana is abysmal.
As of 5.16, this game has officially power creeped far enough that singed is no longer relevant.