Have you actually read the link you're providing as source?
It doesn't explain what it means to have "taste buds tuned" for water, just that dogs will drink more after eating salty or sugary foods, which could be entirely unrelated to the actual taste at all.
Even if these taste buds functioned like what you allege, they wouldn't be tasting water, they'd be tasting chemicals (flavors and smells) dissolved in the water.
It doesn't explain what it means to have "taste buds tuned" for water, just that dogs will drink more after eating salty or sugary foods, which could be entirely unrelated to the actual taste at all.
Even if these taste buds functioned like what you allege, they wouldn't be tasting water, they'd be tasting chemicals (flavors and smells) dissolved in the water.