Nofollow was a reaction to sites that allowed spam but didn't manage or clean them, and the early SEO game of trying to get links on any and every high page ran

Nofollow was a reaction to sites that allowed spam but didn't manage or clean them, and the early SEO game of trying to get links on any and every high page rank site - and buying/selling high PR domains. It allowed a link without giving any pagerank love to it. Setting nofollow until a link has enough votes, on a site that manages spam well, seems like an ideal way of handling it. No point using HN to boost your 5 page adsense sites (when those were still a major thing). Shouldn't affect crawling though. Crawlers crawl sites that update often more frequently, and did IIRC long before nofollow. So HN and popular news sites like NYT, BBC, Guardian etc are probably being crawled near constantly. A new (followed) link should show up frighteningly quickly. (This is all assuming Google haven't remade nofollow to mean something different now pagerank doesn't really count for much any more.)