I'm saying the quills should disappear, so you don't have to collect them again. That doesn't fix hunting for quills if you happen to die, but the solutions to that are a) deal with it or b) git gud. It's a collectathon, looking for things is kind of the point. If you can't find the last quill, explore more and enjoy the world a little bit. You'll eventually find it. And when you do it'll be all the more rewarding for your effort, rather than just handing the player everything with no work.
I won't complain if they decide adding phantom quills is the right move, I just don't see the point for several reasons. I think they'll look out of place, might confuse new players (invisible platforms can be made visible, phantom quills would look similar but react differently to the same moves), make the game easier for no real reason, and most importantly the worlds seem too big for it to be beneficial anyway. As it is, the quills we've seen are just sort of there. They don't lead down paths like they did in BK. Notes were more or less just there in BT as well, very few lead to paths. And the nests of notes were often hidden like a secret.
Edit: Notes -> quills
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