Pick the right TV size for your room based on how far you sit, using SMPTE (recommended) and THX (immersive) viewing-angle standards.
The right TV size depends on field of view, not just distance. Industry standards:
For 4K and 8K TVs you can sit closer than with 1080p without seeing pixels. If your TV doubles as a gaming monitor at close range, go larger than SMPTE recommends.