I’ve added some permalink to some mislabeled segments. Note that the surrounding segments are the correct speed limit. Both of these segments are in a neighborhood where the speed limit is universally 25mph.
Wrong -> Right
https://www.waze.com/en-US/editor?env=usa&lon=-77.36882&lat=34.76317&s=70360341&zoom=5&segments=35938458
35mph -> 25mph
https://www.waze.com/en-US/editor?env=usa&lon=-77.36024&lat=34.75446&s=70360341&zoom=5&segments=35935261
20mph -> 25mph