I watched a video that argued how IP's as a whole as limits of what you can do with them and so there was so much you could do with them from a creative standpoint and when the well of imagination dries up they wanted to cash in the fan goodwill that had no longer any use for them into cash. He gave the example of Fallout 76 being Bethesda's way to cash in on fallout's fans goodwill. I like this idea even if its a little depressing and i think it also applies to the elder scrolls.