And there were several posts immediately after the original link that rather disparaged the principles of the rating system.... yet no response to the last Daily Posts article.... Interesting....
Not sure why you find it 'interesting'; it's fairly common for topics to dip, especially when a number of points have already been made, none of which the Daily Post article actually addresses.
The Daily Post's latter article actually puts all the points into perspective and gives the rating system the credibility it deserves. However, I have actually eaten street food in India, Thailand, Indonesia, Sri Lanka, Malaysia many times and love it. I once enjoyed a plateful of fresh prawns grilled over a small brazier at the side of the road by a street vendor whilst enjoying a cold beer in Bangkok. I was contemplating another delicious plateful when I realised that the prawns were being supplied by youngsters on the other side of the road fishing through a grid into the storm drain. Once in KL I was enjoying grilled spicy chicken whilst watching a rat have a tug-of-war with a cat over a piece of offal. The rat was bigger by a factor of 2, but the cat won.
Some of the finest Asian food I have tasted has been from street vendors and shacks on the beach. Happy days.
The other factor to consider is that in Asia, a far greater proportion of food is eaten out; some living accommodation for office workers I saw in Bangkok was built without kitchen facilities, and people exist on street food which has a very fast turn-over, getting their breakfast on the way to work and supper on the way home. The vendors rely on repeat trade and the food has to be good, fresh, and cheap, and there is a huge variety to choose from. I rather doubt that a hygiene rating would be of any use there.
For one of the best curries available in the UK, try the Ghurkha Restaurant in Brecon, owned by a former Ghurkha and his wife.