Blame the inevitable next recession on government attempts to make the tax system fairer. Nice try, but it won't wash. The downturn will affect more than just Canada.
Our tax system is supposed to levy equal taxation by income. It is class prejudice to give some people special treatment based on the notion that their way of earning income is particularly noble. You can smell the self-regard in Rosenberg's article and in the comments full of self-congratulation about taking risks and creating jobs. Business people think themselves so much better than us mere working folks.