First of all this is not bashing thread about the new expansion (yes, i know Blizzard reads this forum as well)
The only reason Blizzard holds back about Legacy is Legion and it's understandable at 100% (profit first), but do you guys honestly believe that this expansion will somehow "save" WoW? Because i don't see how this will ever happen, even if they nerf this... low lvl content being "hard-vanilla-style". This won't prove anything, once you hit lvl 40 or so you'll be able to 1-shot mobs around and not having fun at all once again. Not to mention the raids, or dungeons for that matter.
If Blizzard really wants to save WoW, they should focus on making Legacy and leave Legion and others upcoming expansions as it is. If ppl really wants to play this content then so be it, simply play on Legion or whatever expansion comes next...
BUT... the real problem/fear that Blizzard will face (because this will happen at some point and the company sees it as a real problem), ppl will be fed with this "easy/god mode content" and say... fuck it, going to reroll on Legacy. At least there's some challenge, and even these naysayers about Legacy will join too. And since Blizzard said they won't be making anymore announcements about Sub status of WoW, this will lead to Legacy/Legion balance 60%/40%, or even more in favor for Legacy.