VTSAX isn’t a free lunch, but you pay in risk rather than time spent managing real estate. It’s passive assuming you can handle drawdowns whereas real estate is passive assuming you think running a rental business is passive.
e.g. VTSAX doesn't have tenants who strip the copper out of the house and leave water running to spite you as you evict them.
VTSAX doesn't have surprise 15k roofing costs.
VTSAX doesn't for you to pay tenants triple if you don't follow / screw up rental laws.
VTSAX has a fairly small fee compared to what property managers charge.