Sadly, this affliction is rampant in the USA. Happily, it is a dwindling number, and perhaps will soon be eradicated.
I wish you were right. I wish it was a dwindling problem, soon to be eradicated. I want to believe that. However, conservative Christians (which should make heads explode with paradox) aren't going away anytime soon. I think you are right that most Boomers that hold these beliefs will be departing in the next decade or so. But they have grandchildren, many of whom listen. I have been teaching middle school geography for ten years. This year was the very first time I had 2 sets of parents question my teaching of the Big Bang as they didn't believe it. I teach at a private school with intensely involved parents so this was not an issue of some parents just happen to start paying attention. While not a strong example, it does lead me to believe that the idea that Young Earth/ID types are fading away is simply not true.
I tell them to turn to the study of mathematics, for it is only there that they might escape the lusts of the flesh. -- Thomas Mann, "The Magic Mountain"