Search engines stopped simply counting links a long time ago. PageRank still flows through links, but what a link is worth depends on its context: what the linking page is about, what the rest of the site is about, the words around the link, and whether the link makes sense to a reader. A link from a page that has nothing to do with you is a weak signal at best, which is why relevant sites matter more than big ones.
Modern search is semantic. Google connects pages to entities in its Knowledge Graph, uses clustering to group pages by topic, and reads the subject of a page, and of a whole site, rather than a keyword in an anchor. A backlink from a site where every page is about your subject arrives with all of that context attached. That is what topical relevance means in practice, and it is the one thing you cannot add to a placement after the fact.
Context is what turns a link into a recommendation.
It is also why we care about information gain more than word count. Each site is built from researched, verified facts about its subject, so the pages say something real instead of restating what every other page says. That is better for readers, better for crawlers, and better for the link in the middle of it. Quality content and quality links come from the same place.
Then there is dilution. Whatever value a page passes, the old link juice, is divided between the links leaving it. On a page selling several placements, you are one share among many. On an EntityLinks site, every commercial link points at you.