Just disabling resting in certain locations doesn't solve the problem.
You can't REALLY solve the problem because "solving the problem" would imply taking a firm stance and making a necessary design decisions which is NOT going to fly with a certain type of user base (you should know which one: the one "I freak out if I hear even just vague rumors of any hard limitation").
So at least creating the inconvenience is a start.
"It doesn't matter because you can always take a ten minutes hike outside of the entire area" isn't really that strong of a rebuttal, because it handwaves dismissively the fact that taking that detour outside of the area to circumvent the impossibility to rest would be annoying and a time consuming, so something that at least mentally well adjusted users would limit doing as much as possible.
That said, if it was up to me I'd be more than in favor of having occasional areas that are both off limits for long rest AND impossible to leave (at least without consequences) until certain situations have been solve.
