Trolling is lying. Either you believe terrible things, or you lie about believing them to make people angry. Normal lying is usually intended for personal gain, trolling is just lies intended to hurt other people.
That is the correct definition of trolling, yours is wrong. It comes from the method of fishing, as in baiting people. It's about getting reaction usually by making people angry or upset. It's purpose is not to hurt other people. Although many people get butthurt over being trolled. BThat is on them. And kind of the point of trolling, "don't waste your time getting upset over shit people, esp people you don't know, do or say. Don't give them power over you". Trolling wouldn't work, if people didn't freak out over it.
Not at all, I think one of the most famous "troll" things he did was buy the master Wu-Tang album and threaten to destroy it so no one could ever hear the album.
There's no lying or anything meant to "hurt" anyone there, but you can imagine that it rubbed a lot of people the wrong way.
Maybe I'm stretching the meaning of lying, but I think it's dishonest to represent yourself as a patron of the arts, as the album was produced as a piece of art, when you're really bidding on it with the sole purpose of depriving others. If that's not the reason he bought it, then he wasn't trolling.