derraleves
YouTube Marketing Expert
That would depend on your definition of self-promote. If you mean spamming "I'm so awesome check out my channel!!" Then no, I think people won't connect with you if you do that, but you have to promote your channel. The chances of people just "finding" you on YouTube and then you becoming YouTube famous aren't good. Know your channel, give good content and build your channel to fit your target audience. There's a lot more to building up a good channel then just adding videos.
I'd consider other social media to be promotion though and there can be such a thing as over promotion.