Realistically, I'm not worried about someone brute forcing my password for some one-off site. On the other hand, there's really no technical reason to limit passwords to anything less than 255 characters, so why do it? What if some technological breakthrough enables us to build processors much more powerful than previously thought possible, processors that can easily brute force a 16 character password? Likely? No. Possible? I have no clue, but I'd rather not gamble on it.