Everyone wants a simpler tax code. Obviously there are a few accountants who are pretty happy for the extra work that labyrinthine tax rules create for them, but to hell with those people. Everyone else, especially everyone running for public office, really wants a simpler tax code.
It is just that actually delivering one is such a problem. Every exemption, no matter how insignificant, has a small group that desperately wants it and those people will campaign ruthlessly for its preservation. It is nearly impossible to imagine support from multiple parties for a real improvement in this regard because no matter what the government proposes to do away with they are taking money from some group that is sympathetic. Maybe they are robbing the elderly, or perhaps it is parents, the poor, family farms, small business owners, etc. etc. No opposition party is going to miss the chance to portray the government as a bunch of heartless bastards trying to pry money from those who so desperately need it.
One thing that really worries me about tax reform is that the people who seem inclined to pursue it are so often trying desperately to find a simple system that crushes the poor. I am consistently blown away by what Republican presidential hopefuls put forward as part of their tax simplification schemes, mostly because they so blatantly aim to improve life for the highest paid people. They use words like 'flat tax' and 'fair tax' and 'equal tax' to suggest that somehow their plans are better than the current skewed system, but they usually fail to mention that, to them, fair means that the rich really need more money. Especially the super rich... because they have it pretty hard, as I understand it.
Simple does not have to mean 'screw the poor'.
Canada is less interesting in this regard because there is not so much support for massive tax reform, nor so much of a push for 'fair taxes'. None of the major parties here are seriously pushing to overhaul the tax system as far as I know, as they all seem comfortable suggesting tiny changes here and there without really tackling the complexity issue in any significant way. Parties promise individual changes to appeal to specific demographics but we don't have crazy schemes to debate like the Americans do from their contenders for president.
If people want a simple system, and everyone does (those few jerkface accountants notwithstanding) then it is an easy thing to create one that doesn't transfer money up the social ladder. A $15,000 universal income and a 60% income tax on all earnings of any type gets rid of the need for most personal exemptions and removes the necessity for much of the current social safety net. Meanwhile, it fixes a lot of the cracks in that system that currently are such a problem. You can also get rid of sales tax too, which removes a bunch of overhead from businesses and irritations for customers, but of course you would have to make up the revenue in higher income taxes. There you go politicians - a super simple tax system that doesn't aim to kick the poor when they are down.
Now go implement it.