That’s a good question. I don’t know if it has an easy answer because everyone’s game is different. The amount of input that the players have on the game world will vary, and as a result so will the DM’s. I’ve played in games at both ends of the spectrum, where the DM decides everything about the world and dictates all options, and where all the participants collaboratively create the game world together, and at every point in between. I have my preference, but I wouldn’t say that any approach along that spectrum is guaranteed to result in either a good or bad game.
Which raises an interesting alternative.
What happens if, during the collaborative worldbuilding, when one player says "No orcs. They're overdone."
Is it still okay for the player to argue about bringing in a half-orc then?
My players are responsible for a good deal of the content in our game. As a DM, I no longer craft a world from top down, detailing everything from the gods to the towns to the guilds and everything in between. Now, I create a sketch and then rely on my players to help fill in the details through their characters and concepts they bring to the table. I’ve found that this actually makes us all more invested in the world, and creates a kind of creativity feedback where our ideas play off each other and inspire new ideas and so on.
Making an expansive campaign setting is how I "play" the game and engage in the hobby between sessions. It's the DM equivalent of making builds and testing characters. Lonely fun.
I've seen collaborative worldbuilding work quite well.
I've also seen it fail. Where the players just want to play and have no interest, freezing like a deer in headlights, and the one or two creative players end up dominating the worldbuilding. (They also seldom make sense. Kingdoms and terrain placed randomly and developing over time, and are seldom logically situated.)
I also think you lose some of the continuity you gain from having a DM created worlds. Where the actions of your campaign and the players can affect the world for an extended time, and even be encountered by future campaigns or even other groups. The success or failure of the party matters: you don't just win and then sweep the board clean.
So I just think that DMs sometimes need to hear that message. You can change your setting to accommodate the players. I agree that a player can indeed change their idea to better fit a game. All I’m saying is that so can a DM.
Story time from my current game. Just to emphasise that I do understand.
My campaign setting is one I wrote in 2e and heavily revised during 4e. A player has decided to retire their PC and bring in a new one, and be a tortle druid. Tortles not being a race I really considered or incorporated into the world. It's super awkward just having turtle people running around.
(The player asked to play a tortle in part because when he ran the
Tortle Package adventure as a one-shot when another player was MIA for a month, and I painted four tortle minis for him to use in that game. And so he wanted to keep using one.)
But that's not a big deal. It's easy to add a tortle. Especially when the motives are known and, well, pure. It's not like it was just the most optimal race to synergize with his build, or he wanted to be special and unique in a lazy way so he wanted to be the only tortle on the planet.
I don’t know if that’s me saying that the roles are equal. I do think that DMs tend to put in more work by default, even if the worldbuilding is heavily shared. Of course, the DMs who’ve written a 25 page campaign guide and predetermined every detail about the world are going to have put in a lot more work.
25 pages. That's cute.
Mine is sitting at 170-pages and I plan on sending it to a PoD site to be printed as a physical book I can place on the shelves alongside my other D&D settings.
(Of course, the moment I do it becomes out of date, as the actions of the PCs will change things and shift the world.)
But what about the enjoyment each participant gets from the game? Shouldn’t that be equal? Just as it would from almost any other social event.
Which assumes all the other players are neutral in these matters.
Which might not be the case, especially if playing in a publish setting.
Almost every published D&D setting has limits. Dragonlance and Dark Sun have class and race limits. Mystara doesn't have gods. Even Eberron, the sinkiest of kitchen sinks, has dragonmarks tied to certain houses.
And that's presuming you're not doing something like
Adventures in Middle Earth. To say nothing about non-D&D games like a
Marvel Heroic Roleplaying or
Star Trek Adventures.
Players playing what they want has to have limits. If the group has decided to play AiME then you shouldn't push to play a dragonborn cleric. If you're playing Marvel Heroic you shouldn't demand to be Batman. And if you're doing STA, you shouldn't request to play a wookie. This isn't unreasonable that you should try and fit the world and tone of the game.
Just like if the group has decided to play a gritty horror campaign, you shouldn't play a halfling bard named
Sprinkles Von Toot Toot.