I've only ever watched a few episodes, but found this discussion interesting (and sad):
In the end, Modern Family turned out to be a show about how a family moves from the upper middle class to the lower middle class in three generations. And the consequence of that downward mobility isn’t so much a drop in standard of living. It’s the breaking up of the family group. It’s loneliness.
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To some extent, this is even the story of my own family; my paternal grandparents owned restaurants. Eventually, they sold those businesses and my dad’s generation are all wage earners. My generation is too, and no one in this family line has achieved the financial success my grandparents enjoyed. We’re all fine and I’m happy with how things are turning out for me personally, but technically we’re downwardly mobile compared to my grandparents. And it’s no coincidence that my dad only rarely sees his brother and I see my cousins on that side even more rarely still. There are many things I love about my family, but this financial part of our story is a cautionary tale.