The tech companies in question (e.g. social media) are not worthless, but they're almost certainly overvalued. Eventually, the market is going to realize this and then they'll be undervalued for a while as a reaction.

It's probably going to go back and forth in cycles between overvalued and undervalued for a long time because no one really knows what the market value of an intangible digital asset is. Can anyone explain how much money the data in the Facebook databases are worth?