"Just get 20% returns easily" LOL! The fact that you would not only think that type of return is consistent and "easy", but literally think that you should go into debt betting on that, is laughable. If it was guaranteed money, everyone would be doing it.

20% return from Betterment? That’s hyperbole right? I have a betterment account and it’s nowhere close to that.

What are you getting? Are you looking at time weighted or money weighted? I just checked and I’m getting an average of 21.6% across 7 different portfolios on betterment (annualized, not cumulative).

The highest is 8.8 which is time-weighted cumulative, annualized is far worse at 2.2 for time weighted

Because they aren't just sitting on the house, they are cashing out after buying and also taking advantage of the market with that money.

Have you checked your portfolio lately?

Yes, and that’s even more of a reason to be putting extra money into the market if you have a ten year+ time horizon.

I'd reference the Nikkei 225 circa 1990 [1]. That graph is not inflation adjusted. Up to 1990 everybody thought Japan was well on its way to becoming the world's largest economy on an exponential and unstoppable economic acceleration. And it was unstoppable. Then it stopped.

I am not saying this will be the case, but rather that we're at what is likely the largest inflection point in modern history, and trying to predict where the world will be at in 10 years has become effectively impossible.

[1] - https://www.macrotrends.net/2593/nikkei-225-index-historical...