Villagers don't always try to claim the closest workstation and are sometimes focussed on a non-existent one or one out of their reach

Check if removing the upper layer of smithing tables and replacing the ones at the bottom changes anything.

I've tried that yeah. I've also removed all of the villagers, tried every other workstation, removed other workstations from the area, cured a zombie villager and put him in the pen, bred the villagers, created an iron golem and went into survival to make sure he wasn't mad at me, etc and none of them will pick up a profession. It's very strange, because in other somewhat nearby areas (30-40 blocks away), on the same y level, they work. They also work at different y levels in the same area.

https://imgur.com/o8vmshE

More info - I loaded up my 1.15.2 backup in 1.15.2 and went to the same area. The villagers picked up workstations fine. Then I loaded the same backup in both 1.16 and 1.16.1 and the villagers do not pick up professions in the exact same spot that they did in 1.15.2. Waiting about several day cycles for both.

It's possible that it might be a weird path finding bug. If I let them out of the pen, they generally path find to another workstation and pick up that profession.

edit: but also, maybe not. no matter how many villagers I put in the area, none of them ever path find/ use the workstations in that area even if they aren't trapped.

yeah pathfinding is definitely not the issue, they just won't use workstations in the area. a couple got lucky and got far enough outside the area that they picked up a different workstation.

https://imgur.com/wCwhfps

Okay, I figured out the issue, but I have no idea why it's happening. Please look at the below video (I can't attach it because it's too big).

https://i.imgur.com/aII1tV5.mp4

Essentially the villagers in this area think they are linked up to barrels in one of my buildings. Before I recorded this video, i flattened the entire area and world edited all barrels out of my world. The villagers all go to the same location and become fisherman even though there are no barrels in my world and are much closer to other workstations when they are spawned in.

Edit: in another scenario, I actually went back into my backup and removed the barrels from this building in 1.15.2. When I upgraded to 1.16.1, they were still weirdly attracted to the same spot and became fisherman again.

Sorry for all the follow ups, but this is the strangest thing I've ever seen. The below video is where I removed the barrels prior to upgrading. 

https://youtu.be/CNIC3HTOm1E

They all just swarm to the building and turn into fisherman...

I found a workaround (requires cheats to be on). Type in the command 

/data merge entity _UUID_ {VillagerData:{profession:"minecraft:_PROFESSION_"},Brain:{memories:{"minecraft:job_site":{value:{pos:[I;_X_,_Y_,_Z_],dimension:"minecraft:_DIMENSION_"}}}}}

where UUID is the UUID of the villager, PROFESSION is the intended profession of the villager, X, Y, and Z are the coordinates of the intended job site, and DIMENSION is the dimension in which the intended job site is in.

I also have villagers attempting to claim workstations that are not the closest, and that they shouldn't even be able to path find to. 

@unknown I'm having trouble reproducing this. Do you have additional information that might help?

The most common situation I'm finding issues with is having a lot of barrels in the general area (even inaccessable ones). I use barrels for a item sorter, instead of chests, and it seems to throw them off the most. Would it help if I uploaded my world save where I showed the issues? I'll try to reproduce in a new world, based on the parameters and see what i can find too.

Sorry, video is too large to load onto this site, so I uploaded it to youtube, the link is below. I know this is a bit of an exaggerated example, but it clearly illustrates the issue and should be able to easily reproduce.

https://youtu.be/FWuI8-jBxZA

I did this with Fabric 1.16.1, with only worldedit installed, to quickly show how this works. It works the same in vanilla 1.16.1.

Sorry, I forgot to remove my texture pack for this, but the lime green villagers are villagers without professions and the cyanish blue color they convert to at the end is fisherman.

This is invalid as it's not reproducible in a vanilla environment. If you can reproduce this in a full vanilla environment, we can reopen.

Man, you guys are really making me work for this lol. Below is a video of me doing the same thing in vanilla. I used commands, so the video wouldn't be 2 hrs, but if you need me to literally place every block by hand let me know.

https://youtu.be/dkrcMSlRjGY

Thanks!

Reopening as the provided video nicely demonstrates the issue.