Consider that not everyone:
- Has a ~100ms average ping
- Has a powerful enough machine to render a full raid in enough detail to stay out of the X in widescreen (widescreen is an under-rated edge in non-trivial encounters.)
- Is up to speed on UI mods
- Wants to make ideal choices for every slot/talent point, etc.
- Talks about the ideal choice for every slot/talent point, etc. for hours
- Can reliably attend a part-time job worth of raids
- Would boot their best friend out of a raid because he sucks at a given mechanic
Those people need compelling content too. Old raid content with toned down mechanics and mudflated gear is one pretty reasonable solution.