Why do you not see more m4/3?

I mostly use full frame but do not always want to carry that large camera. I recently had to decide which smaller camera system to "upgrade." What a first world problem.

I have a Panasonic m43 dSLR at least one generation off current. I like the size but with the 14-140 (?) zoom it weighs as much as an APS camera. That camera works well at base ISO but noise is an issue much above that and based on the images posted in camera tests on this web site has only somewhat improved in current sensors at ISO 800. The 4/3 ratio requires cropping for many print formats which requires lopping off a significant amount of the limited pixel count or "pre-cropping" when framing the image, ditto for viewing on the ubiquitous 16:9 ratio monitors. Eye level EVFs have improved but for me remain awkward compared to direct view through the lens. Finally the smaller sensor mandates shorter focal length lenses which impose aesthetic and technical restrictions although the inherent greater depth of field at shorter focal lengths increases the illusion of accurate focus.

So I got a Nikon D3300 to replace a D5100. This camera is small and light, has a technically better sensor than is available in m43 and I can mount my  better glass on it (albeit with the crop factor penalty). Win win. I don't have a 4k HDTV and only shoot video snapshots anyway.

That being said I think m43 is fine for most uses but can not beat the marketing problem of having "only" 16mp despite that being about 6 more mps than most people will ever need or use. If you do not understand the limits of smaller focal length lenses that is not a problem and if you do not understand the advantage of direct optical viewing that is a non-issue. Most people do not dial up the ISO or print at large sizes so m43 sensors are not a problem for them.