It depends on TV size. If you've ever experienced Netflix on a 75" TV, 1080p content looks mediocre on it. So really it's better expressed as "there isn't much benefit for most TV sizes."

I wont quite argue, that 1080p is always enough on a 75", but your example is more a Netflix problem; their compression results in hideous quality, and it's not really representative of what 1080p could be.