Actually, ALL of those instances you mention were enormously annoying back then. Carol's absence was known well in advance, as was the Elizabeth Shue replacing thing, but that didn't make it any better. If you really want to cite SUPE 2 though, cite how they've got some joker doing a Gene Hackman impression through most of it, because Hackman wouldn't come back and loop his lines for the new director (though I admit I didn't know the reason for the weird voice till a couple years late ,it was annoying as hell.)
Maybe it is because attention spans ain't what they used to be that this notion of your came to be. Pre-internet and pre-DVD and pre-laserdisc and pre-VHS, people were still audio taping movies and buying the scripts if they wanted specific enhancement beyond what they saw in the theater.