I imagine other terms might be both accurate and descriptive, but "Lane Splitting" has the benefit of already being a commonly applied term. In the photo, if it were the motorist passing a bicyclist, indeed people would refer to it AS lane sharing.
BTW, people on bikes frequently lane split as well. Typically, it involves riding up along the right side of stopped traffic (with or without a bike lane), hoping nobody is going to turn right at the intersection or into a driveway. I know of nobody that thinks this is perfectly fine, unless there IS a bike lane. Somehow, that makes it all OK.
The multimillion dollar question is: Why is it illegal (except in California) for a motorcyclist to share a lane with a motorist but bicyclists are cited for not encouraging motorists to lane split?