Never heard of “Tier 1” NAT, so I’m not sure what that’s doing, but the necessity of using NAT at all inside your home network is extremely uncommon.
Heck, NAT aside, even having two subnets in a home network is pretty rare 
WINS support only adds Name Resolution across subnets … it doesn’t provide for Master Browser discovery across subnets.
But to track your point, even WINS is horribly outdated… most systems made in the last 10 or 15 years now just default to using DNS for NetBIOS name resolution, and only use WINS if they get a negative response from DNS or local NBNS broadcasts.
At my company, we haven’t deployed a WINS server in YEARS, but we continue to support old ones because we have Windows NT boxes still online…
Yes, your situation is VERY niche.
The use of direct UNCs is favorable in a lot of instances, but subnet broadcasts will work in the VAST majority of home networks…
