Yeah but this tool just lowered the barrier-to-entry for any motivated attacker. What before was an, oh, 20 hour slog through a bunch of sites looking for the same username, is now a 15 minute run of a script.

For an analogy, consider another tool, an app you can side-load and use to unlock any Prius made between 2010 and 2013. Is this beneficial? Certainly some affected Prius owners will be helped by its release. But affected Prius owners will be (probabilistically) harmed. Even if you're one of the group that was helped (probably arguing the exploit was already well known prior to the tool's release, perhaps?) I think it is dishonest to assert that the release of the tool is "good" from a utilitarian sense.

I wish it weren't so.