That’s the same reason we can’t go back to the moon. ???

Edit:

The new animation style is all digital now, but the truth of the matter is, it is impossible to do the show now the way it was done then. The hand-drawn animation, the water colors, those don’t exist anymore. If they exist, they certainly don’t exist at a cost where you can do a TV show.

So to save money, they threw out supplies they already had. These guys are tasked with reviving a show but given none of the tools or budget to do so. And if they fail due to lack of investment from Disney they will still take all the blame.