Good fake engagement would be more convincing and harder to detect.
Instead what you see is a post from a fresh account that is a copy/repost of one of the top posts in either that or a sibling subreddit.
This is then followed by a half dozen accounts reposting the top comments from the original as their own comments. This is often where they mess up and it's easily detectable when not the OP responds as the OP.
If you check back in a month or two or so, the accounts are inevitably banned by Reddit or shilling something somewhere else (with a minimum age/rep requirement) themselves and/or using the accounts to express support for something shilled. The "resume writer" was annoying prolific.
I find it doubtful that Reddit corporate is using such an approach to try to drive up engagement numbers.
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.
