I only agree that if my camera isn't capable of reducing exposure by one stop and I need it, then the only proper thing is to use ND filters to reduce the light. I would only use ISO 50 in a pinch, and that wasn't available on many bodies.
I won't agree that 1/8000th isn't needed. If camera A offers that and camera B doesn't, it becomes a feature I have to add to the list for consideration of what to buy. You don't need IS for macro shots, or live view, or a tilting LCD, however having it makes the shoot easier and possibly then more enjoyable.
This one stop shutter, in itself, is probably very near the bottom of the list of what you use to consider one camera vs another (like the 6D vs 5D3), but it is indeed a feature that is on the list.
Enough said at this point, I presume?
Some want 1/8000th, others don't need it, much like dual slots, or 61 AF points vs 11, or joystick vs not having one, etc.