I get the frustration, but it still would to put pressure on them. Because even though the data might have been scraped/bought, it means that people would not go to reddit to find information, as it'd be deleted/worthless.

So yes, it's acknowledging that you can't take back the scraped data, but you can at least poison the well for others who would use it.

And yes, it would harm current users of reddit. That's kind of the point, because I don't think reddit makes any significant changes unless they get significant pushback from the thing they're trying to sell -- #s of users.