Do you think you'll ever have kids?
I had friends that lived in small tenements. I had friends that grew up in the projects. 4-5 people, less space. Did fine.
One good book: _American Project_, by Sudhir Venkatesh.
I don't think anyone would debate this, however, I doubt success was ever really limited by the amount of living space they had growing up. Having lived in the "bad part" of a "rough city", square footage had no bearing on future success.
Now, we are family of five with a dog. We live very comfortably in 1400 square foot house. That is less than 300 square foot per person.
Square footage is overrated. It is all about maximizing your usable space. As added bonus, we spend less time in clean up and have less clutter to keep up.