Nobody can predict the bottom, or how low things will go.

But I disagree that valuations are very low. Frankly, many tech companies (Uber, Twitter, etc) are still unprofitable money-losing machines with high valuations because of their potential growth and expectations of future profitability. There's an argument these companies should be worth much, much less.

For the past ~10 years in particular, investors haven't cared about profitability; a market downturn may change that.

Also, as the recession or depression continues, advertising is going to get scaled back and may destroy ad-tech companies like Alphabet/Google and Facebook.

Your prediction is as good as mine, of course. But I'm a bear, expecting a river of blood to flow through the streets of Silicon Valley.