This also explains why it's impossible for incumbents to unseat the winners in many search categories -- because they've literally been picked as the winners by humans at Google.
Looking at my Twitter/X feed, I also see an oddly similar dynamic. Certain accounts appear to have been manually boosted, showing up all the time -- whereas others posting even the same exact content will never appear.
Silicon valley will loudly tell you all about how wonderful they are at "democratizing," however, if you look under the surface it appears they're just hand picking the winners.