It's an excellent article, and the work within is very well done, but there's a part of me that screams "Why would you introduce this much complexity for what should be a simple scroll?" (overcoming technical hurdles to produce the desired end result aside).
OP is doing a basic analysis on what kind of solutions exist for a typical UX edge-case. They even provide the simple solution that most people use (margin-bottom).
And for fun they go on to see if they can solve it without the minor drawback of the simple solution.
We've got to stop acting like it's a badge of honor to avoid UX consideration. We might not be people who implement UIs, we use UIs all day and should be able to muster up a few opinions about how a UX interaction should work.
UX is in the gutter with extra clicks and terrible workflows in almost every website. UI is a catastrophe of mobile first, but not really, but sort of kind of we want power users but we need regular users, and all our UI kits look like total ass that is incompatible with so many other things.
This website is a great example. The webpage doesn't load instantly and instead forces the user to wait for text to appear. Great UX engineering guys, make the user wait!
The entire web stack – backend and frontend – is a mess because the nature of the web is cumulative development over two decades, leading to a pile of abstractions upon abstractions that by some miracle remain mostly interoperable and backwards compatible.
Which is what I loved about this article - it demonstrates a sizeable effort resulting in a UI implementation that is just not much better than having callouts / figures in the text- and then admits it.