sys-auth/nss-mdns provides: /usr/lib64/libnss_mdns.so.2 /usr/lib64/libnss_mdns4.so.2 /usr/lib64/libnss_mdns6.so.2 /usr/lib64/libnss_mdns_minimal.so.2 /usr/lib64/libnss_mdns4_minimal.so.2 /usr/lib64/libnss_mdns6_minimal.so.2 /usr/share/doc/nss-mdns-0.8/README.gz /etc/mdns.allow net-misc/mDNSResponder provides: /usr/sbin/mdnsd /usr/lib/libdns_sd.so.1 /usr/lib/libdns_sd.so /usr/include/dns_sd.h /usr/share/man/man5/nss_mdns.conf.5.gz /usr/share/man/man8/mdnsd.8.gz /usr/share/man/man8/libnss_mdns.8.gz /lib/libnss_mdns-0.2.so /lib/libnss_mdns.so.2 /etc/nss_mdns.conf /etc/init.d/mdnsd I suppose that /lib/libnss_mdns.so.2 and /usr/lib64/libnss_mdns.so.2 will get messed up, because both are inside the searchpath sharing the same name.
amd64 needs a newer net-misc/mDNSResponder stable, its libs are installed into completely wrong location.
As far as I can tell no platform has marked any more recent mDNSResponder stable yet
I just looked over the newer Versions and I think that by providing the opportunity to add a "mdns" target to /etc/nsswitch.conf they will still collide.
multilib-strict itself is not a reason for stablization. that being said, 107.1 has the same issues. kde herd, this is yours.
Latest ebuilds mutually block each other now. If I should have overlooked persisting multilib issues in 107.6, open a new bug, please. Thanks for your bug report Matthias.