No follow can be just as important IMO. Especially for getting direct targetted traffic through social media. Though it won't affect your seo.
Are nofollow links good for Search Engine Optimizations?
Course without them you could hurt your site by having an unbalance.
If you have no no-follow links you will have an unnatural link profile, as everyone else has been saying make sure its from highly relevant traffic sources.
Focus on getting people to your site not influencing the search algorithm.
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