I personally have some blogs that's not really SEO optimized. But it has some readers already and that's good enough. Optimizing SEO really takes a lot of my time and comparing to the cost and benefit of having ranked first on Google search doesn't mean much to me.
Well, in the end, it will completely depend on the person's intention. If a blog is a certain person's main source of income, then of course he/she's going to take extra more time and effort to optimize SEO, in contrast to the other blogs which are just made mostly as a hobby.
Bitcointalk is big enough already, I don't think trying to get first on every SEO-related website is a good thing to pursue too. And anyway, I believe the lack of good bounties contributes more to the traffics compared to the merit system in general.
Yeap, in this case I really don't think SEO matters that much for Bitcointalk at all(even though it ranks #1 on the "bitcoin forum" search query anyway), as it is
THE Bitcoin forum anyway. I don't think anyone even suggests the bitcoincom forum(rightfully so).