Regardless how to define what's garbage and what's not, YouTube seems to remove demonetized videos from recommendations. Since I don't think that good content is always necessarily advertiser-friendly, a lot of good videos are just not getting any attention because a few big companies decided that they're not helpful to market their products. Example: Historical or educational videos which are about controversial topics or just have the word "war" in their title.

Basically, their recommendations algorithm favors profit from advertising over personalized recommendations because it seems to be designed to maximize click-through rate and watch time for videos with many ads. [1]

[1] https://youtu.be/fHsa9DqmId8?t=838