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NIST proposes barring some of the most nonsensical password rules
(arstechnica.com)
This is a most excellent place for technology news and articles.
Some kind of upper bound is usually sensible. You can open a potential DoS vector by accepting anything. The 72 byte bcrypt/scrypt limit is generally sensible, but going for 255 would be fine. There's very little security to be gained at those lengths.
I do 256 so I hopefully never need to update it, but most of my passwords are 20-30 characters or something, and generated by my password manager. I don't care if you choose to write a poem or enter a ton of unicode, I just need a bunch of bytes to hash.