80% of stock is owned by the top 1%. They have to put their money somewhere, so the market keeps rising.
The way to fix this is to raise marginal tax rates back to pre-Reagan levels, and close both the "stock as salary" and "loan against unrealized gains" loopholes.
Tax all income the same, wages, interest, and (realized) capital gains. Require banks to treat loans against unrealized gains as unsecured.