The Wikipedia article you quote states that as the possible earn-out over a 15 year period rather than the 5 year period you suggest. Overall collection costs as quoted in those documents are roughly 2.7%, which isn't wildly off what you might pay for credit card processing fees. I'm no great fan of the license fee myself (although I haven't heard of a compelling alternative), but cost of collection isn't a strong argument against it.
You're completely right - I misread that period. Thanks for pointing that out. I'll leave my original comment so your correction still makes sense.
I do, however, think that a minimum of £73.3m per year (£1.1bn / 15yrs) is a disproportionately large figure to pay for license fee enforcement. I absolutely think that the high cost of managing the license fee infrastructure is a good argument against the model, and the removal of those overheads (and others) may offset a some of the lost revenue.
A change in licensing model and overall culture (which I do understand has been attempted several times in the recent past) might result in a more universally appealing BBC. I struggle to find BBC programming very compelling, particularly when compared with other domestic and international broadcasters. They always feel... out of touch.