It's a good point - I'm not sure who really thinks of reddit as a secure and private platform. Warrant canaries certainly make more sense for gmail or dropbox or something.

That said, while your behavior regarding reddit might not change, it could inform your political behavior. Since organizations can't say they've received NSLs, it's really hard to survey and see how common it is. I'm glad reddit's case here is gaining interest, and hopefully other companies will take part in this program and also get attention when it happens. It would be good to know just how prevalent this practice is.