What simplicity? Houses aren't limited from being off-grid because of 120vac conversion efficiency, and the new hotness in batteries is HVDC which makes charger

What simplicity? Houses aren't limited from being off-grid because of 120vac conversion efficiency, and the new hotness in batteries is HVDC which makes chargers cheaper because it aligns battery voltage to common DC MPPT voltages from solar panels. The industry has been literally moving away from low voltage DC recently.