Bitcoin has attributes superior to gold including its portability, divisibility, seizure resistance, liquidity, and verifiability. Try sending gold halfway around the world and assaying its purity within minutes, a practice Bitcoin enables with ease.
Bitcoin is the quintessence of scarcity, as it is the only globally tradable asset that has a known fixed supply cap. Other scarce assets like gold and real estate have irregular production schedules, and new gold mining and construction technologies may lead to a supply glut in the future.