You don't seem to understand how this game is played. You keep 10% of your portfolio as liquid money or near liquid assets. This means a rise in asset values increases your dry powder. But since dry powder doesn't go down in value as fast as other assets, you get to buy all the distressed assets on during the fire sale. That is the essence of speculation.

If a 4% mortgage crashes housing prices, your money goes that much further, but you only benefit from the crash if you have enough money to buy the home outright. If you must borrow part of the money, then you must pay interest which means you aren't getting a discount on the house, you're paying the same monthly payment but some of it is going to the bank.

A crash in asset price only matters if you're required to convert those assets to cash while the asset price is deflated. If you have significant assets and cash you aren't required to liquidate those assets, so a relatively short term drop in value isn't actually that important. What is more important is having liquid assets, or the ability to get loans, that allow you to buy new assets while their value is deflated.

You only actually lose if those assets actually fail, and if you have significant assets at the beginning of a recession you also likely have a reasonable spread of assets so are unlikely to actually have a significant proportion of your assets actually fail completely.

This is something people really need to understand: those "losses" reported for the extremely wealthy are only on paper - in general they have not suffered any significant permanent loss.