Most people, including pros, don't expect the battery to last ten hours for moderate use. They only depend on the battery to last that long for low-intensity stuff, which might include writing, doing email, etc. Those pros who need more time unplugged for moderate use get an external battery pack. It's math, can't do much about it.Not talking about real heavy duty. Just talking about non-idle scenarios.
Besides: you consider light use like streaming video and browsing as what most people depend on? I seriously doubt that. After all, this device is intended for professionals (hence the "Pro" moniker).
Or at least it once was, no idea what Cupertino is up to nowadays