I have no problem with people self voting genuine own posts and comments (after all the whole point of buying Steem is to give more visibility to own posts/comments) but I believe it is an abuse when the self votes are directed at bots/copy&pasters.
Here is a bot/copypaster who's been milking the introduceyourself posts for over a month now:
https://steemit.com/@steemik/comments
and the proxy upvoter:
https://steemit.com/@inuk/curation-rewards
if you have any doubt his reponses are automated, he clearly didn't read this post before posting his welcome:
https://steemit.com/introduceyourself/@sunil.gupta/introducing-an-imposter-creep-and-a-cheat-on-steemit
in that same post a few more abusers were exposed
https://steemit.com/@aluma/comments (scroll down for the upvotes)
the upvoter bot has been inactive the past 5 days (probably since the API went down)
https://steemit.com/@noaommerrr/curation-rewards
and some welcomebots/copypasters don't even bother to use a proxy voter and just self vote
https://steemit.com/@predictor2100/comments
https://steemit.com/@zinasura/comments
https://steemit.com/@tomino/comments
If someone really reads an introduceyourself post and offers a pertinent welcome to a new steemian and then upvotes himself I think that's perfectly fine and still good for Steemit as a whole (giving newcomers a real human welcome is valuable).
But there shouldn't be any self voting going towards bots and copy&pasters, and such upvotes should be countered.