Two ways I can think of offhand:
1. Make the changes, but represent them more clearly as an evolution or transformation of the old domains, rather than "this is how it always was." Explain how old became new. (I almost wonder if this was the intent at some point in development, since Valachan comes close to this.)
Except that may not really work.
I Cath had basically nothing but an adventure local in 2e. No city, no inhabitants but Tsien and her daughters, and some monsters that were magically created when you rang the bells. There's literally nothing to evolve in this domain.
For Falkovnia, the assumption I've seen is that the domain would be broken up and his ministers become darklords in their own right. So you may end up with a dozen or more tiny connected pocket domains instead of one big one--which yes, would be an interesting idea, because if you escape from one you'd just end up in another one. I might even do this, have the ministry buildings be connected domains and any soldiers are mostly generated by the Mists and there's no actual
war, even if anyone thinks there is. Then I'd keep a slightly modified Metrol as my war domain. But that's not an evolution of the domain. It's a reboot that keeps the problematic elements of racism and slavery.
For Dementlieu, if you assume that Honaire is gone, then the next darklord would almost certainly be The Brain. And while this would likely take care of Honaire's rapiness, The Brain has the
exact same powers as him, so there's that whole consent thing again. If I'm right and that's the reason why they didn't keep Honaire, then nothing is solved with this evolution.
And with Valachan, well, there's been no real set-up for who would take over, except maybe Lady Adeline. But she's an S&M serial rapist, so that's another thing that isn't really appropriate for an official book. Or maybe one of the Black Leopards, but they mostly uninteresting bullies. But either of those would change the flavor of the domain a lot, enough to make it a reboot, not an evolution.
So... could they have "evolved" the setting instead of rewriting it? Probably. I'm sure the writing staff could have come up with a way that gets around my problems. They're clever. But
should they have? We still have the same problem that I mentioned before--it's the same world, just a bit farther, so why bother buying it?
And it
still wouldn't stop the people from getting mad at the changes. I read a review/Let's Read of VRGtR on Fraternity of Shadows where the reviewer was unhappy that they used the word "torment" instead of "curse," believing that this was an example of sanitization. Even though, quite frankly, torment is a much stronger word and a lot of the darklords were barely affected by their curses.
2. Simply don't update domains like the above, leaving them as fodder for DM Guild or fan projects. Then use those new domain concepts for actual new domains. That way you get the new, fresh ideas, without implicitly asking veteran fans to pick which version of Ravenloft they want to use (they can just pretend the old favorites are somewhere out there in the Mists).
And
then you'd have the problem of people complaining that those domains are left out, and people complaining that the new domains are too much like the old ones. "Why didn't they just call it Falkovnia?"
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