Does this imply that you think an important or principal reason why players don't play their characters as wanton murderers is because the GM will bring in-fiction consequences to bear?
I will tell you this - I've played some GTA in my life and I know, that despite being a player who focuses on the narrative and story of the games, GTA very easily incentivizes you to go on a rampage by the fact you can go slaughter everyone on the street and get freaking army after you...and once you get out of the hospital, it will be as if nothing happenned. I have seen people go on similair rampages in Skyrim and how little it matters - nothing bad will ever come to the protagonist and all NPCs whose death would render the main plot unplayable are immortal. You can rob someone blind and then sell them their own stuff if they didn't see you take it. And people do abuse this freedom of consequence in those games simply because it is there. I do not care for this type of gameplay in my tabletop sessions and if I were forced to play at such table, I'd rather walk away and not play at all. If this is the direction D&D is going towards, then maybe D&D is not for me.
I've not said that anything is bad. But I do have my own preferences for RPGing. And GM-provided "plot hooks" and "quests" are not among them.
I dread how delusional the answer I will probably get, but I'll bite - then what do you want from the game instead of plot hooks and quests?
Also, the "I didn't say it's bad, just that I dislike it" just means "I've said it's bad but I don't want to be confronted about it, so let's chuckle it to my personal preference".
But anyway, I talked about me as GM working with players to establish backstory etc. I didn't say anything about who has "ownership" of those elements, who may be at liberty to change them, to reveal them to be illusions or false rumours or whatever. But it is precisely the ownership aspect of bastions that you are criticising: you want this player-created element of the fiction to be fair game for the GM.
GM working with the player to establish something should go both ways, that's what cooperation is. You are defending Bastion as a thing where player is all take and no give - they get new fancy thing that DM has to give up control over, and DM gets nothing in return.
I didn't say anything about me assigning a deity to a cult from a backstory. I said "Do they see their explosive-obsessed Dwarf as something like a Tinker Gnome - in which case presumably the forgotten temples are to Reorx and the Greygem?", and went on to talk about working with players to establish the backstory, setting etc elements. It would be the player doing the assigning, not me.
Sounds to me like you are already limiting the player chocie, you just made a bit of mental gymnastic to pretend you don't. By naming existing gods and adhering to setting lore, you will have players who consider it too limiting. On the flip side, you will have a player who will consider anything but a page of lore to be homework and tell you it's your job to make their concept fit. And none of these is bad, btw, so spare me "don't play with players who don't play the game I, rando on internet, play them" comments.
As to whether or not it is bad for a GM to want to keep a number of gods limited - I don't think that is bad. Nor is it bad for a player to want to introduce a new god. It's probably not possible to satisfy both those wants at once, at least if they are understood literally. Hence the need to work together.
Except you don't want to work together, both previous paragraphs seem to be "just let the player do it", whenever it means giving them unlimited freedom or offloading to them the work. Why ever DM if you don't want to put in the work?
And before you say anything, I work 4-shifts job. I've worked the same physical labor job before I begun running my current games, next year I will switch to ones where I will be doing 12-hour shifts. And I still consider that GMing requires work and I gladly do it because so far it is the only REWARDING work, and fun me and my players have is worth it.
It also seems to me to have the potential to be more than colour - besides the minor benefits the player might get for their PC from the productive activities that occur in the bastion, there is the possibility that the PC establishes a reputation related to their bastion, which then matters to NPCs they meet. And other stuff like that.
The Bastion cannot develop a reputation because Bastion is not part of the world and DM is not allowed to interact with it.
None of these ways the bastion might matter to a player in play is undermined by the fact that the GM can't make it into something that is at stake in play.
It's not just abotu being at stake, it's about all aspects of being part of the world. You have too antagonistic view of the GM, where the only way GM could ever want to interact with a Bastion is to do something bad to it, when by these rules I cannot interact with it AT ALL. Traders cannot show to set a trade in the bastion, refugees from war cannot seek asylum, people cannot hold festival there - DM is not allowed to interact with the Bastion. It's not part of the world, it may as well not exist when players not looking at it. Schrodriger's bastion.
