True and now imagine that 70% of the web is accessed through mobile devices today. The format of these web stories is basically identical to a vertical phone, I think they exist so mobile users browse through more content more quickly.
These decisions may not seem to make much sense for us now because browsing on a desktop always feels more efficient but they aren't designed to be efficient for us, they are supposed to be efficient for a somewhat desinterested mobile phone user who was going to click away but now he or she sees a flashy little story and thinks "eh ok, I'll watch what they want". Google may even envision a future where the normal search list results are an advanced feature and regular users all prefer to click on stories because that's where all the offers and gimmicks and easy to digest information is in. Ever since I underestimated TikTok, I am a little more careful to dismiss these new developments. In a way, these mini stories are another variation of tiktok mini stories.