A case for a hypothecated poll tax?

Over at the Telegraph Shane Richmond comments on private-sector media workers' antipathy to the BBC's funding structure that "there can't be many other industries in which you're legally obliged to fund a major competitor to the tune of £135.50 per year."

And the more I think about it the politically odder the funding structure for that unique British institution (that Mencius insightfully calls the Department of Journalism) appears. It's a hypothecated poll tax. That is, a flat fee levied per head of population by the government to meet a specific spending objective.

Which to say the least is something of a political anomaly, since anyone who paid even the scantest attention to the political climate of the early 1980s would presumably concur that the current government would run a long, long way from the implication that it operated a poll tax, and our current administration has consistently opposed hypothecated taxation for all sorts of other purposes on grounds that, according to our last PM, "a hypothecated tax is still a tax that comes out of general taxation". Every schoolboy knows that poll taxes are regressive and end with rioting in the streets. Even our last PM knew that the money collected into the public purse is all the same money, however you describe it, cut it or spin it. And yet.   

(Yes, technically the license fee isn't quite the same as a tax because in theory you can opt out by not owning a television, a strategy I pursued for about five years back in the early 90s. Still, acquaintances who live without a television to this day report that the license detection people react with often aggressive incredulity to the claim that there's no TV in the house, and from my limited experience the choice to go TV-free is sufficiently concentrated in the upper demographics as to merely exacerbate the regressive impact of the levy.)