Those I've used in the UK aren't so bad, they're cold fill only with a heating element in the sump. It takes maybe 15 minutes to fill and get up to temperature at the start of a shift, after that each cycle is ~2 minutes.
The hot water is recirculated during the wash, the rinse uses fresh water from the tap with the excess going out an overflow.
A little sump water gets replaced every cycle, but enough stays that it's back up to temperature before you've emptied and refilled it.
There's also a small peristaltic pump to top up the detergent directly from the bottle.
Not much benefit in a home setting unless you fancy having it hot and ready 24/7 though.
They also have the clever system of standardised, removable baskets. Need to increase dishwashing throughput? yank the clean basket, line them up on the counter to dry, and run a new basket through
This is probably the one trick consumer dishwashers should emulate
The problem in basically any consumer kitchen is storage - having racks and racks of stuff under your big stainless steel commercial countertops is no problem.
The hot water is recirculated during the wash, the rinse uses fresh water from the tap with the excess going out an overflow. A little sump water gets replaced every cycle, but enough stays that it's back up to temperature before you've emptied and refilled it. There's also a small peristaltic pump to top up the detergent directly from the bottle.
Not much benefit in a home setting unless you fancy having it hot and ready 24/7 though.