ok, so lets focus on the non technical aspect:
the main problem @arhag mentions is the ¨payout farming:¨ abuse.
Often a discussion is based on some kind of not really tangible fear, so lets first look at the worst case scenario, that everybody is self-voting, so that we know what exactly we have to fear..

All the steem that is newly created for post rewards in the end is payed through inflation by steem / steem power holders. The more you hold the more you pay. If all would only self vote in away in the end you only get what was already yours. But that is not truly the worst case. Even worser would be if only some part of the steem holders take part in the voting process. In this case you could get some part of their cake if you selfvote. That said this worst case scenario does no sound that worse. At worst it would be some kind of micro payment platform where you can distribute your money to posts, even if they are your own posts. In the end its mainly your money you distribute. In this scenario only passive accounts would loose money, but that sounds also ok, as long as the time period they have to distribute ¨their¨ money is long enough, lets say 30 days.

Now after seeing that this worst case scenario isn't that bad, lets further look how we could even improve that:
Simple self voting itself is easy detectable through the transparency of the block-chain, so we only have to look at sybil-voting where you use more then one account. Simply creating some accounts that vote circular is also easily detectable, so they would have go through some kind of hiding strategy like using an exchange. All the time they would risk, that their self-voting strategy becomes known. In this case they could get flagged. Currently without having the ability to flag users, we could simple flag the posts of the sybil accounts and or shadow vote the sybil account. In this case they would need 2 years before they could transfer their steem power to a new unknown sybil account.

Summary:
If nearly all would just selfvote, In worst case we have a micro payment platform where you can simply distribute your ¨own¨ money. Creating Sybil accounts and hiding them is not that easy. Every-time one Sybil account becomes known you risk to loose the ability to vote for two years through being flagged / or shadow voted. In this case you would loose more then 10% for your steem holings through inflation. Under the promise that most of the main steem holders would take part in the voting at best self voters would get what was already theirs , at worse their money get trapped for two years and on top of that they would loose 10 plus percent of their steem value through inflation. That does not sound that promising for Self Voters...