Specifically https://www.hpi.uni-potsdam.de/hirschfeld/publications/media.... I read through it once when you mentioned it here a few months ago, but I think it merits a deeper reading, which I haven't finished doing yet.

I think more than necessity, requirements, and fatality we have more of a gradient thing. It isn't necessary to have no syntax to do compile-time metaprogramming, but the effort gradient sort of pushes you in that direction. It isn't impossible to write a web browser in Forth either, just hard.