"Most popular" and "what makes most money" coincide here. It doesn't matter in the least what companies say at a given point. If Ubuntu proves to be more popular both for gamers and workstation users, hardware manufacturers will simply follow. This is so obvious I shouldn't be even writing it.
No, they will support what will make them the most money. They are corporations, they care about making money. If they will gain (or lose) more money based on their wayland support than their mir support (which is in line with their own statements about where their money comes from), then they will support wayland. And vice versus. Popularity contests only matter with geeks, what matters to corporations is money. And those are not necessarily very closely related.