A conservative tax protest is a protest that taxes are too high, too onerous or illegal. A left-wing tax protest is a demand for more taxes on someone else. Or, in this case, a baseless accusation that someone else isn't paying enough taxes.
It's hard to think of a better way to summarize the fundamental differences between conservatives and the left when it comes to big government.
Conservatives protest for more freedom. Leftists protest for less freedom. Conservatives want to keep their earnings. Leftists are convinced that all their utopian projects don't have enough money from the money tree because the "rich" aren't losing enough of their income to big government.
Conservatives want fewer chains. Leftists insist that the problem with the chains is that not everyone is chained down hard enough.