I hate to sound like a broken record but since you elected to push this thread to Trending, I am going to take a shot at a little exposure.

The principal problem is the lack of counter-upvotes. These cost money. Upvoting stuff that was (will be DVed) hurts your investment. Your HP is going to earn less. For 99% of accounts, it makes no financial sense to protect the value of the platform that way. Among the top 1%, it might make sense but other business models are viable. That is why I pitched the DV incentivisation plan. Having more DVs in the system is a side-effect. The primary motivation is to allow people UV someone that is being nuked without losing money off their own pocket.