I know they can do it. But that doesn't mean that it should be done. Even if they manage to write a really good story, and they probably will, telling that story is wrong in itself. Good writing isn't just about writing a good story, it's also about knowing what not to write.
This feels like what Hollywood does with constant sequels. Like what Disney/Marvel did after The Avengers: End Game. They can't let go of characters like Thor and Captain America, even though their character arcs are over, so they keep finding excuses to pump out new sequels and bring back old characters whose stories are over. It's the same with The Witcher 4. The Witcher 3 was Ciri's story as much as Geralt's, and her story was told. It's over. She became a witcher or she became an Empress. We don't need to know what happened next. Let it go.