The Internet is a natural eco-system. The moment you create a site that has an artificial pattern to it, that site becomes suspect.
The more sites following that pattern, the more obvious the artificial pattern becomes. The more obvious an artificial pattern, the more likely Google’s systems will mathematically laugh in your face.
Note that this is sometimes seen as a pure one-time direct penalty. Yet it’s also often a case where the lack of on-site SEO refinement and the lack of quality off-site signals combine to create a situation where you’re going to see problems for a long time, and not isolated to a single event.