I keep telling my boomer parents to get out of their empty "larger" house NOW, while they can get the most for it. Even if it means going into short term lease/rental unit. I'm afraid the market may take a downturn and/or they will have a hard time unloading it for a decent price. They want to downsize and retire out of state eventually.
Also, I am a DINK millennial with a <2k sqft house, yard, 2 dogs. Not too small/too big for us and we have zero plans to have children. Wife is 30, have a few years to change our minds but at this point its a no.
I keep subtly encouraging my mom to consider moving soon. After my dad passed, she is pretty stuck in her ways to not leave her house. I think in a few years, she'll be more open to the idea. The house is more than she'll ever need now. 4 bedrooms, huge yard, big basement....doesnt need all that. But I dont want to push her to any drastic changes just yet. Shes still extremely mobile and enjoys that freedom.