I don’t know for how long, but I just used it and it worked.
If you waited to wipe your account until after the protest started (like me) there are likely a bunch of subs that were private, and your comments weren’t deleted. It’s worth checking again to see if there are any comments you missed.
It should work indefinitely. It doesn’t use the same API that third-party apps were using, it uses the user API that is used to browse the site, basically just using the permissions a logged-in reddit user account uses.