This has already happened in China, where Baidu (The Chinese equivalent of Google) can’t crawl any articles from WeChat (The Chinese equivalent of Medium), as a result, the usefulness of its search result has deteriorated significantly. Recently, Baidu has been trying to start its own publishing platform with little success.
Also food ordering, travel reservations, health care appointments, banking, government services, and a whole lot of other things that would take too long to list. It's not an exaggeration to say the entire Chinese consumer experience runs through WeChat.
