If I were Google, Here's how my algorithm would find paid links

I can only speculate, but i'd imagine their algorithm finds and ignores paid links the same way a human can easily sniff them out.

If I am google, my question is "did this website organically "vote" for this article to support their own article, or did someone pay them?

my guess is that part of their link value assessment algorithm includes:

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1. Number of linked domains by the linking site - A site that links to a bunch of sites in an unnatural way is probably selling links
2. Edit history of the article - if an article was written, sat stagnant, then it is recrawled and the only edit to the article is a link placement on existing text with no context or value added to the article, that would be easy to sniff out as a paid link
3. Anchor text - there is absolutely no unincentivized reason for any website to link like such "best lawn equipment" "attorneys in denver" etc. That is so fake and easily detected its not worth it any more.
4. Quality/rankings of the linked to sites - There is very little natural reason for a website to link to a blog that is not already ranking itself. How do people find sources? they google something and pick a ranking article to cite (its a catch 22 i know because you need links to rank and you need to rank to get links)
5. Patterns of reciprocal linking and link webs
6. Link acquisition patterns - If a website suddenly acquired 1000 linking domains overnight, they are buying links (and could be selling them too). They either bought PBN or an expired domain or both beyond a shadow of a doubt
7. rankings, organic traffic, and niche relevance of the linking site. If I get a link from a DA 75 site with zero traffic, it will mean zero to Google. Google didnt rank them, why would a link from them carry any weight? If I get a link from a DA 75 site with 100,000 monthly users from traffic link "best gambling sites" "how to hack" etc. and I am a lawn care company, that link won't help either.

Try to think like Google when you're building links. I'm not saying don't buy links, I'm saying don't buy links from crappy sites.