[gruez]

But if 16 characters is already secure for the foreseeable future, why bother risking it for negligible gains in security?

[pferde]

That's something each of us has to determine for themselves.

I haven't yet, in my many years of "being on the web" encountered a single website with the truncated password problem described above, so for me, it's a weird statistical anomaly to be ignored.

If you have been burned repeatedly by some such websites, you will have a different outlook, and will generate your own passwords accordingly.