Dollar-cost averaging into the Nasdaq for 30 years—can you really stick with it? But the moment you bring up paying off a mortgage for 30 years, everyone suddenly has extra energy.

Investing in the Nasdaq for 30 years will definitely yield higher returns than buying a house—however, don’t even talk about being able to “stick with it”; most people won’t do that.
Other than the fact that a house lets you live in it, it really isn’t a question of returns.
Paying off a mortgage for 30 years is painful just to think about—but that pain is certain. Even if most of what you’re paying is interest, every installment means you’re one step closer to being done.