Actually, validation is for mods that are to be published and distributed. This effectively kills "only fun for myself" mods, but it's a price I'll gladly pay.
Of course, that is a developer decision to make. However I hope that decision is made after considering both the downsides as well as the upsides fully.
The main point of my post is that the public mods and the private "just-screwing-around" or just testing mods are not removed from each other. Affecting one will have consequences for the other. And I believe for the whole mod down the line which is why I bother to write about this.
To use another game as an example; Let's take TES:Oblivion under examination. It still has a lively community built around modding and adding still more content into the game, even though it has slowed considerably. Would this ever have happened if modders could only access some kind of sterile testing environment with their mods, and never use them in the mode that they enjoy playing, which would be the main story mode for Oblivion, unless they published them and had them signed by Betheseda?
If Crpg now is like Oblivion from the perspective of modders, what would happen to it with the tinkering mods killed?
The game would be a much more locked down one, a game with not much freedom for expression.
Such a game is much, much less likely to attract creative types, a critical resource for a community driven game.
The obvious complaint about the above analogy is that Oblivion is fully offline, and not in any way comparable to an online game. To this I would say that it's an analogy, dummy, and analogies are never perfect. The main concern between offline and online games is cheating and if the cheating aspect of this was game breaking, Crpg couldn't have grown so popular and retained that popularity for years. With the biggest concern gone, I believe we can dismiss the complaint.
The difficulties in developing mods would also require more technical skills than they do now. You would either need the resources and know-how to run your own server, or at least access to someone who can do those things for you. This is a lot more required right at the start, compared to simply firing up Blender or Photoshop.
We have artists and visionaries and other jack-offs amongst us, let's not dismiss what they could offer to the mod because they are not as technically oriented.
Consider the open-source community. How much of open-source programs are made just for the needs of the developer? Originally made just for their private use? And maybe published after months or even years of polishing and private use, if it comes to that. If we stomp out tinkering, we stomp out the effect that gave the world Linux and countless other programs.
This would be the hard path to take, and asking much more of the devs. But I believe it is also the right path.
Just like politicians that can't decrease military or anti-terrorist funding, because they would take much flak for having done so if something bad happens, developers will come under fire for having the tools to stop all "cheating", and then not using them. It will be annoying.
But it just might be that small thing, that hidden factor, that causes or enables a positive feed-back loop that raises Crpg above the grey masses. After all, the easy moddability of this mod made the creative community that has gathered around it and has been partially recruited to further develop itself what it is now. I believe it would never have happened if tinkering was harder, and it would be a mistake to underestimate the future effect of this seemingly small change.
I will understand if it is decided to kill off non-whitelisted mods, but I'm afraid it will also be a nail in the coffin of the enthusiast spirit in this mod.