man ssh: [...] -6 Forces ssh to use IPv6 addresses only. [...] While on my system it does not force it - it only use IPv6 by default, and if it is not available, then ssh fallbacks to IPv4.
That is a bug on your system then (possibly in your resolver). Could you attach a debug trace from a session where it falls back to IPv4?
No reply = closed bug.
Mass change of RESOLVED bugs to CLOSED