Disney could have drawn upon the EU that had grown around the IP, but instead they decided to discard it completely.
One of the problems with Disney's SW shows is that they can't create anything that stands on its own. Everything has to be a sequel, or a prequel, or an interquel, or explore the adventures of a movie character, etc. Even the Mandalorian suffers from being an offbrand Boba Fett show with cameos by legacy characters.
The animated anthology Visions is the only production that doesn't suffer this problem. While it does feature the Empire, the jedi, and the sith to the exclusion of other potential plots, it doesn't feature any legacy characters. Unsurprisingly, this happened because Disney gave the directors complete creative freedom. Some of the stories don't feel appropriate for the universe, like the jedi prodigy who slices a Super Duper Deluxe Star Destroyer in half with his lightsaber while breathing in space like Captain Marvel. But overall it shows a fraction of the potential that Disney fails to explore.
But to be entirely honest, trying to turn SW into an EU franchise was doomed to failure from the start because it was never intended to be one. If you want a franchise universe, then you have to build it from the start as one, like how original TTRPG sandbox settings are designed. You need to build in plot hooks and so forth, otherwise the writers will be left hanging and not have any idea what would be appropriate for the overall tone of the universe.
Multimedia franchises that were developed ad hoc by accumulating various detritus from various writers over the decades will always be inferior to settings that were created to be sandboxes from the start. You can see countless examples of this in how every franchise that develops this way falls apart quickly. Alien, Terminator, Predator, MCU, SW, etc.
Not only that, but even if you do start with a detailed sandbox setting you still need competent people to develop for it. Games Workshop has Warhammer Fantasy and Warhammer 40,000 but has consistently failed to develop any of it into a multimedia franchise despite the setting's incredible (and underutilized) flexibility. Rather than focusing on how you can tell novelty stories involving all the really weird but interesting stuff that appears nowhere else in the setting, the games and streaming shows have used only the clichés of the setting.