Oh... So it's impossible to stop all npc's from spawning?
I did search, but apparently was searching in the wrong place. (I think I'd been searching the bugs for scrolls, or something).
I realized my mistake after I'd already submitted this, and I then re- searched the right area and found that what I'd just said was a duplicate. I came back to mark it and found that you'd already done so.
Sorry! (And way to be quick and efficient! 🙂 )
Ah, I see. That's what I thought "Mob" referred to, so I was confused when Mustek seemed to imply that only hostile creatures were affected by the gamerule...
As for the issue, however, I had remained in almost exactly the same place for nearly the entire time while villagers kept spawning. All the chunks in a very wide radius around me had long since been generated. Therefore, there shouldn't have been any new chunks generating at the time. In fact, there shouldn't have even been any changes between which chunks were loaded and which ones weren't. And I certainly wasn't spawning any villagers. This is why I found it unusual, and reported it as a bug in the first place...