True, and HTML5 video tends to "just work," however I've found that many people have practical issues with hosting their own video. For example, not understanding video conversion, hosting behind bandwidth or request rate limitations, or not having anycast/CDN set up to hold the site together when a page unexpectedly goes viral. There are reasons that hosting videos yourself might not be an effective use of the resources or time available to you, especially based on technical skills, in which case third party hosting with pinning remains a better option.