From a European pov: I get the feeling that more and more people are finding their favorite non-Champagne-region <i>méthode champenoise</i> (<a href="https://en.wikipedia.org/wiki/Traditional_method" rel="nofollow">https://en.wikipedia.org/wiki/Traditional_method</a>) wines for a lot less than "proper" Champagne and don't really see a reason to pay through the nose for the trademark.
This reminds me of the article discussed here a few weeks ago that Wine Sales are down in California:<p><a href="https://news.ycombinator.com/item?id=40947332">https://news.ycombinator.com/item?id=40947332</a><p>I think consumers are turning to other beverages - spritzers, seltzers, mixed drinks, etc vs wine and champagne.