Can a McMansion come between friends? From an advice column four years ago:

Dear Prudence,
My husband and I are moving to the city where one of my dearest friends lives. She really wants us to move to her neighborhood (“You can walk over for barbecues! Go on morning runs together!”). I love the idea of being close, except I hate her neighborhood. It’s a bunch of huge McMansions with things like fake turrets and nonsensical designs. I get why she and her husband chose it—there’s lots of space for their big family—but you couldn’t pay me to live there. On paper, though, it makes a lot of sense: It’s close to my work, in my price range, etc., so my friend doesn’t seem to catch on to my polite demurrals (“That might be a little too much house for us” or “We’re looking in a lot of neighborhoods.”) What can I tell her besides “your house is hideous”?
—Hideous House

Unless she’s calling you every day and going through all the listings in her neighborhood, I think it’s fine to keep offering her polite-yet-accurate demurrals until you eventually find a house elsewhere. There’s a natural expiration date to this conversation, and that will be when you move into a house in a different neighborhood. In the meantime, you can stress how great it is that you two will finally be living in the same city. If you absolutely can’t stand her gentle but insistent questions, then pick a household feature or two you know her neighborhood can’t provide that are absolute necessities for you and tell her: “We’re looking for something with less than 2,000 square feet, and [your neighborhood] just doesn’t fit the bill. Tell me what you think of these two houses we’ve been looking at.”

The term McMansion is typically negative. The answer above suggests it is best not to call out the friend’s home as a McMansion. This might not go over well, even if the person picked the McMansion because they liked it. Instead, emphasize how your own interests are different and move on.

I have wondered about this very topic for years: it is one thing to dislike McMansions from afar or in the abstract. But, what happens if someone you know and/or like lives in a McMansion and likes it? Is having a McMansion a barrier to friendship or a deeper relationship? Should one who dislikes McMansions express this opinion and the ways that McMansions bring blight to the earth? How does it work to criticize McMansions strongly and then know that at least a few McMansions like them and purchase them? Are these sorts of differences part of the sorting of people into different communities and social spheres?

These dynamics play out regularly in many communities, whether they have subdivisions full of McMansions or teardown McMansions. How exactly they affect interpersonal and community interactions and relationships could be studied further.