Version-to-version differences are typically covered in documentation form, not in tutorial form.
The Helpdesk has an article for
GMS 1.4-2.x differences.
Of course. Which is what I've used to get up to speed on GM:S 1 through 1.4, and GMS2. The article you quote was my main source of understanding the differences in GML between the two. Some people learning by doing, though (and other's learn by reading first-principles, which is fine too).
The point I was trying to make is that the magnitude of incremental differences are big enough between 8 and GM:S, 1 and 1.1, 1.1 and 1.2, etc. that reconstructing all those differences is still non-trivial. But it's definitely doable, since that's what I've done already.
Why is it so fashionable these days to believe that all answers lie in tutorials, and forget there are such things as articles, documentation, independent thought and common sense?
It's not either-or, though. We don't re-derive every principle and technique from first-order principles. Roundups of changes, abstractions that define generalized principles from a bunch of lower-level principles, etc. have been at the core of most types of education we've had since the 20th century. See for example the
ICAP learning hypothesis.
But sure enough, I had already conceded that the market for people benefiting from such tutorial style is probably not big enough to warrant it.