My point is more that Pascal was abandoned by its author, which happened while it was still widely used. (Or that was the external perception. In the Oberon project, sure, they may have had a Pascal front end for all their own old code to work.)
Wirth made a mistake by fragmenting his language development over similar, but incompatible languages under different names.
When we look at C, the story is different. ANSI C was carefully designed to be backward compatible with K&R C. C99 didn't break too much in C90: test cases to demonstrate incompatibility have to be contrived. The name of the language didn't change.
Simply not changing the name is a powerful social tactic. People overlook differences when the name has not changed. (Look at how Lisp outsiders think that Lisp is all the same.)
Modern Fortran is very different from Fortran 66 or 77. Because the name is the same, the "Frankenfortran" is accepted in the same circles (e.g. scientific computing). Had the name changed, that would be unlikely.
I can't escape the suspicion that Wirth should have continued to use the Pascal name for that entire succession of languages.
GCC just integrated Modula-2 into their compilers in the box offering.
A bit of Oberon survives in Go, which is probably the only reason I somehow like the language, despite their design decisions, which I must admit are still less draconian than Oberon-07.