Link bait seems to have cropped up in 2005, Nick Wilson has the earliest mention of the term I have found, although I have not looked that hard. The point of this post is not to detail the history of linkbait, nor how to do linkbait or even what is linkbait.
There are far better people than me to go into that lot.
Lets take it from another angle.
You’re at a dinner party and someone says “You know, I really think George Bush is actually quite bright”. Everyone stops talking, mouths are open, everyone stares at the speaker. Of course you may not find the statement that shocking, but here in the UK it would be quite a bombshell.
The dinner party then descends into a somewhat heated debate about silver spoons, Harvard and Neo Conservatism, amongst other things.
If it was on the web they would label it linkbait.