Yes. A massive implosion in aggregate consumer demand due to shrinking population will hit real estate, stocks, tax revenue, and therefore the ability to meet debt repayment obligations.

Frustratingly, (and counterintuitively), it won't help housing prices, because shrinking populations retreat to city centers. Spain, Italy, Japan, and Korea are full of $5,000 houses. Meanwhile, Madrid, Rome, Tokyo, and Seoul are more expensive than they've ever been.

Most stock market trades aren't made by people, but by institutional money. That ain't going nowhere.