My opinion on the matter is that the appeal of a van to a lot of people these days is that of functionality. Meaning, they might not have a surplus of income, and/or spare time apart from just trying to eat, keep clean, work, and pay whatever essential bills they may have.
Therefore a simple, cost effective, low maintenance, mobile shelter is all they desire...I personally have come to appreciate vehicles in stock form for many of the reasons listed above along with ease of repairing/parts sourcing. I always have and always will do all my own repair work - minor or major, was a Ford dealer mechanic for a bit but got out of that. I usually even change my own tires by hand, and I'll say that stock steelies and factory size tires make that process A LOT easier than custom wide or large sizes!
The "no build-build" appeals for many reasons, and can make a utilitarian living space transformable into a cargo van or work van within an hour...and back again...or mix a combo of all 3 into one
Super quick to clean, and also easier on the mind to let it get a bit dirty if need be.
There will always be creative artists in the world who enjoy modifying and creating cool things - it's something I surely admire about them! But in the grand theme of my book it's rather pointless, adds complexity and maintenance issues while being time, money and resource consuming...all counter productive to a minimalist lifestyle. I'd rather be relaxing, hiking or gardening.