AI trainers do a lot of work filtering and reformatting the training data. Often that's the most expensive part. There's a lot of synthetic data used these days too, reprocessed by other AIs.
spez says that's how he got reddit off the ground in the first place: faking content/engagement (well, genuinely engaging with his account(s?), but essentially shouting into the void and hoping enough people heard and wanted to stick around.
with a RedditUserBot trained on reddit users, you might be able to fake another decade of growth.