I've had this same issue - sometimes the raid can't seem to find a place to spawn even though there is an area for it.
One of my friends said the problem is we generated this world during the snapshots for Village & Pillage, apparently outposts can't generate so close to villages anymore?
If you'd still like the seed/coords let me know and I'll get it tonight - the chunks were generated in snapshot 18w?? - not sure on which number.
For me when I got back into the world after crashing the shulker was duplicated - it was placed and at the same time an identical shulker was still in the dispenser.
Is it intentional fortresses generate so much less often than in previous versions? In 1.15 our nether had at least 8 within 1000 blocks of spawn, since we deleted the nether chunks for the 1.16 snapshots so they could generate anew it has 1.
I can confirm this in multiplayer too, whenever the server is restarted the datapacks need to be reloaded using commands, they aren't working by default anymore.
Edit: The part of our datapack that changes the blocks endermen can pick up doesn't work even after using /reload. The rest of the datapack still works. Everything worked fine in the previous snapshots.
Agreed, a timeout where they then try another workstation would definitely help. Imo they should also try the closest unclaimed workstation first, since normally when you're breaking and placing them you're trying to get a villager that's nearest to where you've put the station.
I checked up on them over the span of two hours or so - some are only a block away (diagonally) from the potential job site, another was enclosed fifteen blocks away from the potential job site they selected, the rest were varying distances, 2 blocks for one, 7 for another, 10 for a third. All job sites were completely sealed off from them (in terms of pathfinding and LoS).
This seems be more of a problem with villagers that are locked into their profession than new villagers.
Just gave it a go - villagers that weren't enclosed by trapdoors do correctly pick their workstations, however the ones that picked their potential job site already refuse to change their choice even if I encase them completely in stone (they've been traded with so they're locked into their profession), they just stare at the potential job site block through the wall and do nothing even though they don't have either LoS or a way to pathfind to it anymore (and they never actually claimed it in the first place, just selected it as a potential job site).
We're having the same problem in the snapshots for 1.16, not on realms but on our server. In our new trading hall half the villagers won't work/restock their trades. When I check their entity data some are assigned correctly (and won't restock even so), however many are either assigned to a job site block belonging to the wrong profession or a position where there is no job site block in the village (and never was one). The problem only started during the snapshots and after we converted the villagers into zombies then cured them. I can't seem to reset their Brain/memory nbt data either, using the data remove command changes nothing.
We've tried everything, moving them around, getting them to sleep, breaking and placing new blocks, bludgeoning them, they just won't update their job site. We managed to fix two by moving them around and breaking/replacing their workstations, so the problem was probably pathfinding for those two; the rest are still broken and have been for several in-game weeks.
Can confirm this still happening a lot in 1.16.1 in multiplayer on hard. A massive pack of pigmen was outside our nether portal and an iron golem attacked them. It spawned about 20 zombies over the course of the fight.