There is no doubt that no-follow links don’t carry the link juice that a follow link does, but at the end of the day linking should be about providing good quality content and being a good net citizen. Linking shouldn’t be just about SEO rankings. I think Google is smart enough to value this in some way.
As you said there's no algorithmic benefit from nofollow links. So that kind of answers your question.
Links in the comment area are also likely to be devalued; search engines have been able to judge the location of links and different areas of webpages for a while now -- thanks to Block Level Link Analysis.