This is very true. While there has never been a bubble without the public markets involved, there has also never been this degree of capital deployed in private

This is very true. While there has never been a bubble without the public markets involved, there has also never been this degree of capital deployed in private markets. I mean that as an investment, in the sense that if I lend my neighbor $5K to start up a farm or something, I have money in the "private market", but I have a firm idea of where it is and how it is being used. This has been historically how capital was in private markets, pre-tech. However, now there are large funds, and funds of funds, taking investor money and parking it into vc & pe firms, as well as companies directly. All of these companies have fees associated with deploying the capital and are competing for a finite resource, driving up the price. The public markets are extremely efficient at whatever they're for now, mainly HFA, gambling, and FOREX liquidity, and warnings that something bad has happened in the world. Or for alerting the world that the FED is making an announcement. They are not used for raising capital to fund business expansion. They are a last resort for dumping a failing company or a forced move because a company scaled out and has hit shareholder max and therefore is defacto public anyway.