It seems to be the time of Lernout & Hauspie: the stock market boom …

Have the stock exchanges gone crazy? On their first day of the show on Wednesday, both food delivery company DoorDash and apartment rental company Airbnb soared on their Wall Street debut. DoorDash will benefit from an ongoing lockdown as Airbnb is betting on reopening the world. Should investors fear the stock market bubble will burst?

Today’s exchanges are similar to those of twenty years ago. Even then, you could throw darts blindfolded and always have a price because stocks were always going up. Surely the newcomers …