1. Only for Elite and up.
Are you talking about having the command be a perk for Elites and above? If so, I disagree since the command would help prevent griefing, and we would want all players to have access to that.
2. It should also plot add people, just to make it easier. It'd be dumb for people to have to add them twice. Which would also happen to completely eliminate the reason for this. I'd have to disagree with this.
I don’t understand how it would defeat the purpose of it? It would make it so accidental world edit griefs are much more common, since a lot of them are on open plots or plots that players need to add a lot of people to (roleplays for example).
This is a very good idea, but I agree to what NaNatNat said. Most world edit griefs are accidental, and if you accidentally make a mistake //undo is always a thing . . .
While //undo is a thing, many players crash before they are able to enter the command, or simply may not be aware of it. I know multiple players who did know the command and didn’t crash, however it just didn’t work due to how many blocks had been placed while they were using world edit.
//rollback is only for staff members. Even ELITE+s don't get //rollback so you wouldn't be able to fix griefs on your plot. Plus you're not supposed to fix griefs staff need to see who griefed the plot. Even if you were given //rollback, you still wouldn't be able to recover your plot fully.
I don’t see where they were taking about players getting rollback in this. I believe they were talking about how sometimes when a grief is caused by world edit, staff are unable to roll back a certain portion of it.
This would make it unfair for the players who bought ELITE or ELITE+ to have world edit. Unless the command only works on people who have w/e
ELITEs and ELITE+s have/bought their rank to make their lives easier. This would drop PZs financial funds if you were able to give people w/e on your plot. People buy ranks so they can have w/e.
All in all, I think the argument that giving people w/e permissions on your plot is insufficient and irrelevant to getting griefed by w/e on your plot. The w/e grief thing is a glitch, and giving people w/e permissions on your plot would make it unfair for those who have bought ranks that have w/e. The better way to do things is to add someone to your plot who has w/e, or ask to do /report to fix a grief.
I’m assuming they meant this to restrict elites and elite+s from world editing on other players plots unless they were added with the world edit command. So no, it would not give random players word edit, it would just make it so elites and elite+s can’t world edit on plots that they are not world edit added to.
The purpose of the command is mostly the opposite of your arguments, it would not add more players that could world edit on your plot, it would restrict more, which
would help players to not be griefed as often.
This thread is half and half, but the thread contradicts itself, if your plot was W/E Griefed, wouldn't /worldedit add also allow players to world edit grief your plot? 
The thread does not contradict itself, the command would only allow trusted players to world edit on your plot instead of just any elite or elite+. That, hopefully, would decrease the amount of world edit based griefs.
For the overall suggestion, I think this would be a great part of a suggestion about a /plot roles command where players could customize specifically what players can do on their plot. I assume it would be defaulted to off.
