Not a solution to carrying passengers, or lots of bags, or in snow and ice, or very long distances, or going somewhere you don't want motorbike gear and helmet to worry about. I love my motorbike but it's not as practical as a car for lots of things.
It's funny - I find cars to be less practical than motorcycles for most of the trips I take, for example whenever traffic or scarcity of parking are involved - which is most of the time! - and if for some reason I could only have one vehicle, I want to say that I would choose the motorcycle, because life without it would suck; but then, a car actually can handle all the trips a motorcycle can make - comparatively slow, expensive, and annoying though the process may be - whereas there are a minority of errands one occasionally has to run which a motorcycle cannot handle at all. So perhaps the real answer is that it's too much to expect any one mode of transportation to handle every need.
Neither are bicycles and electric skateboards, but needs must. With cars costing tens of thousands, not to mention parking issues, I see a great many young people turning to two-wheeled vehicles in years to come. A small motorcycle, be it IC or electric, will always be the cheaper option.