If there are better replacements in general, then you will be inclined to replace things more readily.
The social analog is that in a community where friends are more replaceable—for instance, because everyone is extremely well selected to be similar on important axes—it should be harder to be close to anyone, or to feel safe and accepted
I can come up with a countervailing effect here, as well. Revealing problems is a risk: you might get help and be in a more trusting friendship, or you might be dumped. If there are lots of good replacements around, then getting dumped matters less, since you can find someone else. This predicts that people in communities that gather similar people might expose their problems more often, despite being replaced a higher fraction of the time.
Another difference between cars and friends is that you’re going to get equally good use out of your car regardless of how you feel about it, but you’re friendship is going to be different if you can credibly signal that you won’t replace it (taking the selfish-rational-individual model to the extreme, you probably want to signal that you’d replace it if the friend started treating you worse, but that you wouldn’t leave it just because your friend revealed problems). In a close community, that signal might get worse if you repeatedly replace friends, which predicts that you’d be less likely to replace friends in closer communities.
I can come up with a countervailing effect here, as well. Revealing problems is a risk: you might get help and be in a more trusting friendship, or you might be dumped. If there are lots of good replacements around, then getting dumped matters less, since you can find someone else. This predicts that people in communities that gather similar people might expose their problems more often, despite being replaced a higher fraction of the time.
Another difference between cars and friends is that you’re going to get equally good use out of your car regardless of how you feel about it, but you’re friendship is going to be different if you can credibly signal that you won’t replace it (taking the selfish-rational-individual model to the extreme, you probably want to signal that you’d replace it if the friend started treating you worse, but that you wouldn’t leave it just because your friend revealed problems). In a close community, that signal might get worse if you repeatedly replace friends, which predicts that you’d be less likely to replace friends in closer communities.
No empirical evidence of any of this.