Not 100 percent sure if this will happen but

There are two matters that give botters an advantage. Attacking a full map to obtain items easier, and usually godmode.

With this system, it would not give them any advantage over others besides time. Sure, a botter may be able to collect all twenty nebulites in an hour where it may take a normal player an hour and a half to two, but they are still only able to produce two nebulites per character. A normal player can just switch characters and continue on getting nebulites.

If that wasn't in place, then it would be much, much worse. Would you rather a botting character to produce two nebulites or a couple hundred.

Don't you know? The botters always win.

It would be worth their time to bot for something else, they're not going to gain much from botting this as it limits the amount of nebulites obtainable per character.