It's no doubt that they've definitely made a profit, even on the worst sequels that've been made. The one thing that the general public has definitely noticed is the sharp decline in Disney animated film quality (both story and artwork). Austrailia was tagged as the top studio for Disney and making sequels, really good sequels that is got them nowhere.
Walt wasn't about how much profit he could make off a film, it was about being original. It didn't matter to him how much money he could spend, if it made it work then that was all that mattered. He didn't consider sequels to original at all, but rather unimaginative copies of an original. Eisner didn't see things that way and his shoveling of cheap-quels down our throats really seem to have disenchanted many people (myself included). The general public doesn't seem to see Disney as the premier animation studio anymore (that honor has fallen to Pixar)...I think the reason that happened was because Disney has released enough crap sequels that people really got turned off by Disney. John Lasseter and Steve Jobs work very much off of Walts motto and are trying to re-establish Disney as the top animation studio and like Walt, are going to be avoiding any and all sequels pertaining to Disney classic films.
I've tried watching as many of the sequels as possible and I can tell you that some of them were sheer torture. I thought Bambi 2 was a nice feature, they even had one of Disney top feature animators relocate to Austrailia to work on it for a year or two (at the time, he was also avoiding being trained in 3D animation). There have been parts in the Cinderella sequels that have had amazing animation, but the stories were very spotty (in my opinion). Tarzan and Jane and Hunchback 2 were probably the two worst animated films that I have ever seen. The story(s) in both were not well developed and the animation in both could have been done by college-level animators.