As I've said in another long post, the champion is filled with noobtraps. People are already terrible at adapting with the champion, but jungle changes with Scuttle made it extremely more volatile. A well-pathed jungler can also be a well-pathed Kindred and does not require marks to succeed! This is unlike pre-bonus AD Kindred, who entirely relied on marks to really do any damage mid to late game.
Kindred does indeed need a rework. But the majority of the goal behind it should be to stop players from falling into pitfalls the champion indirectly encourages you to walk into. Pursuing marks instead of counterjungling, building Runaan's or IE not acknowledging when these purchases are still valuable to the champion compared to other options, not building BoTRK as an alternative option...like bruh, it's not even surprising why the win rate dipped. Riot is to blame for making the champion, the players are to blame in that they aren't learning properly. But Riot calls "burden of knowledge" an anti-pattern, so it does fall to them for the responsibility at the end of the day to fix this issue.