A much better analogy is this:
Shops and businesses have established themselves over time in large numbers on the costly land in the commercial district at the centre of a city. They are paying handsomely for the privilege, and are happy/willing to do so because of the prestige of the area (great footfall, credibility etc). If they come onto the market at all, plots of land in this area exchange hands at high prices. Land in other parts of the city costs just a tiny fraction of the going rates for this prime commercial space, but the price reflects the benefits and it remains highly sought after (and completely occupied, with wall-to-wall businesses jostling for space)
Suddenly (with no prior warning) every single property sinks into the ground overnight until only the flat roofs are sticking out, flush with the ground. A layer of tarmac is poured over the submerged businesses, and the "new land" thus created is sold anew.
Sure, you can still "get to" the old businesses by going down from the street into the basement of the new properties, but they've instantly lost the prime locations that they had spent all that time, energy, money and resources establishing themselves on.
Doesn't the above sound absolutely bug-eyed crazy? How could ANY of the affected businesses have anticipated that? Can you imagine the stink that would be raised if such a plan were even hinted at? Yet it's as close as a real-world analogy to direct.uk as you're likely to find.
After all, Nominet willingly worked arm in arm with businesses, government, end users, domain investors, secondary market platforms, etc. for close to two decades to establish .co.uk as THE business extension (backed by regular surveys that they proudly trumpeted to prove the effectiveness and value of the extension) - then tried to sweep the extension aside as a "second best" choice by bringing in .uk over the top.
I believe that the direct.uk proposal did catch a lot of people, even very experienced hands, by surprise by virtue of how ludicrously misguided it was. In business, you sensibly plan for every foreseeable likelihood - but it's the very rare business indeed that plans for insane, completely off-the-wall things that logic dictates could/would never happen.
But hindsight makes for a great stick to beat people with, doesn't it? Especially if you've got some sort of an axe to grind against domain investors anyway because of some misplaced sense of entitlement/feelings of being hard done by. All these "Well, you should have guessed this utterly nonsensical, ludicrously unlikely scenario was going to sabotage your business. Ha ha! Serves you right for being so blinkered. Sucks to be you" posts are pathetic, spineless revisionism after the fact.