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.
Still unable to find sources for your claims?