In this case, the owners of both are the same. My guess is, if one goes poof the owners struggle for liquidity, selling other assets.

Most of the people trying to find a home in canada arent also in the market for a home in china and vice versa.

This reads more like they expect to be forced to sell by legislation or other outside circumstances soon and want to try making more money before people lnow they have to exit soon.

Bitcoin should go up when USD and the economy crashes logically, but it goes down (also it’s a ponzi scheme so it doesn’t need to make sense). For the same reason this isn’t true, people sell other assets when they take massive losses in one category and become insolvent. Liquidity and value of assets lower accross the board generally in this interconnected world economy of the modern era.