It probably isn't on Disney+ for the same reason The House of Mouse isn't: the show is a logistical nightmare when it comes to residuals.
And don't forget that, like the main film and its DTV sequels, it would probably the same content "warning" telling people about potential stereotypes and distasteful scenes that could be present in the show.
That's unlikely, Disney replaced Robin Williams with Dan Castellaneta for Return of Jafar and the TV series due to a fallout between Disney and Williams regarding contracts (IIRC it was advertising-related) and being the latter costing less. Williams returned to voice Genie in Forty Thieves but another Disney-Williams fallout occurred after it released which caused Castellaneta to "permanently" inherit the role until he was replaced by Jim Meskimen.
But look at Hercules. Stacked cast of people
Tate Donovan, Samantha Eggar, Sandra Bernard, French Stewart, Robert Stack, Jennifer Jason Leigh, Jane Curtin, Betty White, Jennifer Aniston, Ben Stein, Lisa Kudrow, Linda Hamilton, Kathie Lee Gifford, Brad Garrett, Dietrich Bader, Will Ferrell, Idina Menzel, David Hyde Pierce, James Woods, Jason Alexander, Miguel Ferer, Richard Simmons, Jennifer Love Hewitt, Thomas Lennon, and Eric Idle.
Residuals out the wazoo. (btw it might just be one of Robert Stack's greatest roles by far. He is the narrator so he's in most episodes and even provides commentary with the muses sometimes)