As you know, Google treats links from spammy sites vs unnatural links differently. But Google also treats different types of unnatural links differently as well. Unnatural links that are classified as "egregious link manipulation" would likely penalize a site whereas other links that are unnatural are likely just ignored by Google.
Gary Illyes from Google said this on Twitter:
That depends on the purpose of that link really, but if it's not a egregious link manipulation scheme, we're more likely to just ignore them
— Gary Illyes ᕕ( ᐛ )ᕗ (@methode) June 2, 2017
Google's new real time Penguin algorithm devalues links and no longer penalizes or demotes links - so this is a similar statement.
Forum discussion at Twitter
