Their pick rates are very high though still - implying they are still being picked into games they should not be as a strategic choice.
If left for a few months people might stop blinding ad assassins every game and only pick them when a team comp supports it, increasing their win rates.
There is nothing that currently proves pickrate and win-rate are correlated/negatively correlated outside of immediately following reworks/reshapes. By this same logic, Zed (8% pickrate and 48% winrate) is MUCH MUCH worse than Veigar (8% pickrate and 53% winrate) in the same meta.