Context is everything in architecture. The rest of El Alto is unfinished, artless concrete and terracotta like the adjacent buildings in some of the photos, so it definitely lifts the neighbourhood, and the centre of nearby La Paz is dominated by concrete towers painted in similarly bright colours that just aren't as interesting. It's the graffiti of the architectural world, and sometimes the neighborhood feels more lively for it.
Not sure it would fit quite as easily in the historic centre of Sucre.
I recently found out that "unfinished" structures in Peruvian emerging towns is by design, as you don't start paying property taxes on a building until is "finished" , leaving it on an eternal state of construction, avoids you those taxes..
Your story may be apocryphal. I live in Peru and the unfinished aspect is rather the result of the extended period (we are talking years) it takes poor families to build their houses and also from the fact that the vertical growth of the house reflects the growth of the family: the children as they become adults build and live on the second floor, the grandchildren on the third etc. These houses are always getting upgrades as the families grow and round up money and therefore are never finished. You can always see the metal rods sticking out of the cement columns because they always plan to add another floor. (Housing in Peru is mostly built on cement and bricks, except the poorest people, because of earthquakes).
Not sure it would fit quite as easily in the historic centre of Sucre.