...If you are allin on btsx or whatever, then you don't want to divest into bitNXT. You are exposed to btsx issues without owning NXT...
I agreed with you at first, but then I thought, "Isn't that true of any BitAsset?". I suppose there is the fact the BitShares ecosystem and NXT are in relatively close competition, so we could have one failing whilst the other succeeds. Then you'd be absolutely correct!
On the other hand, some may believe that BTSX will continue to work well (and want to support the DAC), but also fancy hedging with NXT. Some may even fancy a small bet on the possibilty of NXT outperforming BTSX!