In many areas of the country it is illegal to build anything but a single-family home. To people familiar with supply & demand this should be an obvious problem.
The intuition behind the LVT is that increases in the value of land, in urban areas, are mostly driven by a growing local economy; therefore the community should benefit from them. Increases in the value of structures, OTOH, mostly come from investments by the property owner.
There's a fascinating book (well, if you have any interest in economics) about the LVT, from 1879, by Henry George: http://www.henrygeorge.org/pcontents.htm
Land is in extreme abundance and multi-tenant properties are almost always built and owned by corporations.
The density is good because it's valuable to be near other things, and density is the only thing that allows more proximity?
Maybe it would help to realize Japan, Korea, and California are all mountainous and prosperous. Mountains helped force good land use (though lately stupidity in California has been beating it).
In theory, a manufactured home community could also be a co-op, and setting one up would be less capital-intensive than building multi-family homes.
It is worth noting that so far as land-use is concerned, MHCs are significantly denser than typical single-family home neighborhoods (even older, denser ones) due to the small lot and home size, absence of two-vehicle garages, etc. They are comparable to the lower end of multi-family housing density due to the parking lots those are typically surrounded with, though of course multi-family housing that has good access to public transit can be much denser.