Exactly this. I would absolutely love one of the new high end LG OLED panels with none of the smart tv features and no network connectivity (privacy & security). I'm really curious how big of a market this would be.

No you wouldn't. There are many niche 'simple high end phone' products, the majority of which fail, despite forums full of people claiming 'take my money', 'I'd be first in line' etc.

The reality is that these products are as expensive or more as regular products (because small batches), and everybody wants a different 20 pct of the full functionality.