OP would need to argue why "Dropped" status isn't sufficient for their needs. This is from a 2015 thread on the same topic, so it at least gives a bit more context and rationale.
Currently I am in the process of adding all the anime on my list on anime-planet and switching my list over, but one issue that I've run into is that there doesn't seem to be a "Won't Watch"(or something to that degree) status. I could probably simply put "Dropped" for such animes, but thats implying I started it to begin with. There are plenty of anime I won't, or can't watch. Some examples of which are Another, Deadman Wonderland, Mirai Nikki, Mnemosyne, Parasyte -the maxim- because gore gives me huge knots in my stomach to the point that I nearly pass out. It'd be nice if I could simply put on my list that I Won't Watch these shows.
Arguments and points:
the main argument against using "Dropped" is the language, the word "Dropped" implies they started the show but didn't like it. But, just putting it in dropped with 0 episodes watched does the same thing: you dropped something without watching any episodes. But, just because a small number of people don't like the wording "Dropped" it's not a good argument for a major overhaul that would affect millions of users.
If you're adding a show to your list at all - you at least thought about watching it, then decided not to, so even if you didn't check out the first episode, you still thought about it, and Dropped it. You also have the choice of simply not listing a show at all if it really isn't something you're interested in, so OP would need to argue why it MUST be on their list while it CAN'T be in the Dropped list.
You could also use tags. Make a "Won't Watch" tag and put that on a show. Presto, done. Now all the shows you don't like are in the same section, Dropped, but you can annotate WHY each show is there with the detail you asked for.
maybe you want the show to be "dropped" so you've got a record of that but don't want it appearing in ANY list? In that case, it might make more sense to ask for a "Hidden" check box on any list entry. If there was a checkable "hidden" option you could private some show listings so they don't appear in your public profile at all. This would have multiple uses, one of which would be tagging shows as "Won't Watch" in your dropped list, but they don't appear in your public profile.