Anything that’s not a household name like Rolex, Omega, Seiko, Citizen, etc…. If I spotted a Nomos Glashuette on a wrist I’d know. An enthusiasts will likely have these brands but they don’t give it away.
The same goes for fashion watches like Invicta, MVMT, Shinola etc… those generally aren’t enthusiasts.
G-Shock can be tricky, even enthusiasts will wear those.
Omega Dark Side Of The Moon Apollo 8 and verrrrrrrrrrrrrrrrrry unlikely. I gots no money.