I can at least talk to you about whether it's reasonable for eg Brian Herbert or (the now-late) Christopher Tolkien to continue to exercise editorial control over their fathers' works, or under what conditions a foundation could be established for the duration of the 90-years-post-author-death copyright the US currently uses.
If it's permissible for Dr Seuss's widow to inherit editorial control of her husband's work along with the copyright, can she pass that control to Dr Seuss Enterprises; if not, could Dr Seuss have established it before his death?
(Personally I think the other reply was better, in stating that it is arrogant to assume that the author's heirs do not know his wishes better than us.)
I guess the widow (or if they are still alive, the editors that worked with the author when he was alive) is the person that probably knows the author best to know if they would've liked their work to be updated or not. Or at least, make decisions on allowing changes that can have impact on how the author is seem (e.g. progressist, non-racist, sexist or not sexist, etc...).
My problem is when someone totally unrelated starts making changes, even in cases where author was explicit that they would never want the gender of their characters changed, and people go ahead and still want to change the gender
Edit: source for what I mentioned on this and my previous comment https://www.irishcentral.com/culture/beckett-waiting-for-god...
The only real counter-argument I can make to the position that the author can edit his works but his heirs cannot is that the author chooses his heirs; the author could have instead chosen to will his works into the public domain after his death, or establish a trust or foundation with a strict mandate to republish his works in their original form while returning the profits to his heirs.
It's not a particularly strong argument -- many authors may not have the resources or foresight to make such provisions, and you could just as easily insist on authors who do wish their heirs to manage their works and not simply profit from them make explicit declarations on that point -- which is why I lead with the more extreme case of an author editing his own work.