I don't think there is a good solution to this. Basically, I'm always aware of the posted limit on the road I'm on (unless if it's a city road wo/ a posted limit in a city I don't travel through often - Oak Ridge, I'm talking to you).
Basically, it's a nice feature that, I'm willing to bet, 90% of Wazers would disable. I would disable it.
Secondly, there is no way to really keep tabs on speed limit data. Sure, you can import it, but that probably has at least some errors, if not many. Why add even more errors to Waze

?
Or leave it to the AM's - but, I can't tell what a posted limit is from GPS tracks, average speed (if I had access), or aerials. Do you expect me (and other AM's) to drive on every inch of road in Southeastern TN (or AM area) just to see if there might be a speed limit sign on a certain stretch of road? (Forgive me if there is a better way to find speed limit data.)
There's no sensible, smart way to implement it. And as others have said, there's no real gain from it, except headache.
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Area Manager: Southeast Tennessee, USA. Includes Athens, Benton, Cleveland, Englewood, Greenback, Maryville, Madisonville, and surrounding areas.
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