I did an Iron farm on a server. put 80 beds, and 80 workstations. There are almost 200 villagers in there right now, probably more at some point. I don't have any other bed on 300-400 blocks arround that place, nor another workstation. As you can see, a lot of them can't even sleep or doesn't have a job, since there's no way for them to do that. Also, a lot of them try to breed and fail, as it should be, while others, right next to them, can breed totally fine.