Why? The question was essentially "how should we determine who qualifies for Indigenous-only welfare programs?"
The article he wrote wasn't to promote discussion, it was designed to inflame certain sections of the readership. "Why those pesky whites pretending to be abos* to gain an advantage!"
(*Sorry)
But more alarmingly, it is accusatory and offensive to the people he wrote about and others with some Aboriginal heritage who are proud to identify as an Aborigine. Who are we to say that they are not?
I don't see any legitimate discussion in what Bolt wrote. If he wanted to promote discussion on the matter, and he did believe people of minority Aboriginal heritage should be eligible, he could have questioned the criteria for receiving awards, schemes and whatnot designed to benefit Aborigines. He could also investigate people who claim to be Aborigines but weren't at all.
To write an article attacking people due to their own self-identification to one part of their heritage just because they don't look the part is disgusting.
Also, on your opinion of the author of that "idiot" website and the apparently Liberal-affiliated intimidation against him, his job and possibly his family, I think the problem is that at least from what I gather, you're basically saying "Well yeah, this is wrong
BUT! he had it coming and he probably deserves it."
No, I don't think anybody deserves to be intimidated for having any political view or for attacking any political party, much less having that intimidation come from anonymous members of said political party. That's pretty messed up shit, and he should probably take the matter to the police, but that's up to him.