When I ran 'port install wine,' I got the "error wine cannot be installed for the configured build_arch 'x86_64' because it only supports the arch(s) 'i386'."
It clearly should be buildable for 64-bit.
See:
if {${build_arch} eq "x86_64" && ${os.major} < 18} {
default_variants +universal
}
if {[variant_isset universal]} {
supported_archs i386 x86_64
} else {
supported_archs i386
}