Facebook and Google face skeptics on Wall Street this week amid digital ads collapse

Wall Street is bracing for disaster in online advertising.

Following disappointing results from Snap last week and a 28% plunge in the stock price that sent the company’s value to its lowest since early 2019, investors are now turning their attention to ad giants Meta and Alphabet as well as reports this week from Twitter and Pinterest. They’ll also hear from Amazon and Microsoft, which have big ad businesses of their own.

The flurry of reports comes at a time of extreme skepticism in web and mobile advertising. Facebook parent Meta shares are down more than 60% this year, and the company is expected to report...