Preservation and innovation go hand in hand
Nostalrius was a Blizz-like server – it emulated how WOW used to be as closely as possible. That didn’t mean slavish adherence to tradition. Some of Blizzard’s later changes proved useful to a volunteer team without a horde of GMs, such as the elimination of ‘wall jumping’ by which players could stick on vertical geometry and climb out of the map. Also, even official servers aren’t intended to host 11,000 players at once, and the enormous server load had to be managed with a system of dynamic draw distances. Whenever load in an area was high, the range at which you could spot monsters dropped off. It wasn’t true to the past, but it allowed thousands to get their fix.