BiS is going to happen no matter what anyone thinks. As long as gear has stats and effects, it's bound to happen. Something is going to be better than everything else in some way that makes it overall "best" for different classes and specializations. The only way to get rid of this is to find a way to ditch gear progression. GW2 has done this, to a large extent, but this makes gear in that game feel worthless - and unless you're in it for the PvP... everything feels like a waste of time. Dungeons aren't really going to drop anything you need, for example, so why run it?
Gear progression is probably one of the biggest issues in this genre. Everyone kind of hates it, but everyone kind of loves [and almost needs] it at the same time.
There is no way to avoid the BiS "issue" unless you make tiered/templated gear like in GW2 - but that comes with some obvious drawbacks.
I think BiS is a great way to get people run content they otherwise wouldn't. This was really useful in EverQuest, because it meant people didn't move off of previous end game content the second an expansion launched. The "BiS" items were so good, that many of them overshadowed drops in the lower raids of the new expansion. This also made it fairly natural to recruit lesser geared players, because you could always gear them up with last-expansions end-game gear without them running into issues trying to get drops veteran members needed. Only the BiS drops posed an issue in this zones (class armor, for example, didn't...). They still did Tacvi even after Omens of War launched. They still did Anguish and ran the non-raid minis for augments after DoDH was released.
I think the issue with BiS, for me, isn't so much that it exists; but that any major content patch or expansion pretty much wipes out your BiS gear. BiS takes a lot of effort to get. I don't like seeing months of farming wiped out in a few hours of leveling - especially when I'm paying to play the game.
I think this manner of wiping out your progress to carrot you along is what has ultimately put me off of MMORPGs as a genre. The games do seem like a massive waste of time, because the developers no longer respect the time and effort you put into building your character.
I remember using my Emperor Ssra robe in EQ on my Mage for about 3 expansions. This would never happen in a "modern" MMPROG.