Nofollow is an HTML attribute value used to instruct search engines bots that a hyperlink should not influence the link target's ranking in the search engine's index. If a search engine finds a “no follow” backlink it will just ignore the link and will not get deeper into crawling and no link juice is passed. So “no follow” backlinks are not important in terms of search engines as it is not crawled. The comments section mostly have no follow links. But that does not mean that these links are useless. You can still get some quality traffic from these also.

Do-follow links are highly recommended for SEO purpose because crawler will index the links which are do-follow. Once the do-follow link is indexed, it will improve the rank of the website on search engine.

Thus, Do-follow is more advantageous as compared to No-follow.