These are not the same:
- “It is a mistake to aim to subdivide that into smaller model/view/update pieces”
- “It is a mistake to ever subdivide into smaller model/view/update pieces”
This is one of many techniques for organizing code. I consider it a serious mistake to apply it eagerly to a broad range of scenarios - that is, to aim to subdivide your program this way, as opposed to reaching for it only on the occasions where it’s the right fit.
SPA pages are one occasion where it is usually seems to be the right fit.