Nope, no demonising. I'll say it again. The dissatisfaction being expressed here - not by me anyway - is definitely not with Americans, or their brilliant creativity with language. I love to hear it and applaud them for it.
It's to do with protecting the 'flavours' of the language, just as the French might protect their myriad cheeses. British English has its own flavour. And when another country's cooler-sounding lingo becomes widespread, that unique flavour is lost.
Posters on Pedants' Corner are generally more attuned to these nuances than on general chat threads. We know most people finds these kinds of concerns baffling and that's why there's a self-mocking tone to the thread name. So on here we get to express these earnestly felt views, that in other contexts might be interpreted as small-minded, the height of rudeness or deliberately hurtful.