It seems that there's no logic to this, just how conservative your controlling agency, POI, etc is.
Your FMS data base probably gets updated once a month and I bet there is some data that gets corrupted every time.
We departed Hong Kong about 10 years ago with an FMS data way point error. It was coded fly by rather than fly over. The aircraft started the SID turn early, so we selected heading and delayed the turn until the correct DME distance out. A following company aircraft on the same departure received a Terrain GPWS warning.
Unless the chart says approved for GPS NAV - then you are obliged to cross check your position using the published ground based aids. Anybody trusting someone else's NAV coded data accuracy implicitly is an accident waiting to happen.