The phenomenon seems to be limited to a certain number of subreddits that are close to a brand or have products to sell. They recycle content to give the impression that there is some interest in their brand, product, crypto, etc. and to avoid giving the image of a dead brand.
Personally, I've observed this phenomenon on r/Polarfitness as soon as the sub becomes a list of complaints and negative feedback about after-sales service, positive content magically appears with very generic content but dozens of comments.
r/AskReddit has been my guilty pleasure for like a decade, and it's super prevalent there too. No products being pushed in the threads I've seen called out.
Personally, I've observed this phenomenon on r/Polarfitness as soon as the sub becomes a list of complaints and negative feedback about after-sales service, positive content magically appears with very generic content but dozens of comments.