Despite the age of the article, it is interesting that Chinese and Indian restaurants can be found almost anywhere in the U.K. French cuisine hardly exists outside the capital.
Also of note is the fact that Indian and Chinese food served in UK, is merely a hat tip to the country of origin. Probably the same in USA where the dishes have been adapted to the local palate and availability of ingredients.
Most quality Indian establishments are often Bangladeshi in origin and staffing at the chef level anyway.
Not ethnic or foreign really, just local adaptations in countries like U.K. And USA where the local menus tend to be more bland and limited.
I suspect Thai food is adapted outside the country of origin in the same way. As I don't eat overly spiced shite here, I am unlike to test this theory in the UK.