There's more variance with small-time landlords. With a corporate overlord you know exactly what you're getting: they are going to be firm about sticking you to the exact terms of your lease and will raise your rent by the maximum possible each year, but you can also expect any maintenance issues to be taken care of quickly and they aren't going to feud with or retaliate against you. With a mom & pop you might get someone really nice who never raises your rent, understands if you're a couple days late, and takes pretty good care of the place; but you might also get someone who is completely unresponsive, violates a bunch of tenant laws figuring you don't have the resources to call them on it, and nickle & dimes you on your deposit.
True, though tenants in corporate owned single family housing all tell me it's closer towards the worst landlords. The corporations won't harass you, but they essentially don't want to do anything. You just get an expensive "as-is" house, which can be okay if it's in decent shape.
Now, maybe he was making it up. But i suspect that there is a common class of dish dirt where prolonged steaming and jetting with hot water is adequate in practice - i'd expect anything water-soluble to dissolve in hot water! So, residues from tea or coffee, water-based pasta sauce, fruit juice, jam, etc. It won't work for everything, of course, but it might work for a surprising range of things.
Well one day it was getting low I poured a new bottle in and all the dishes weren't getting washed. I called the detergent company to report a defective bottle, but turns out there was some sort of formula change due to a new regulation. Apparently mixing the two together in the auto-dispenser causes them to harden and clog the dispenser. So I tried just pouring it into the manual dispenser, slightly better but the dishes weren't really clean. I called my dishwasher repairman who just told me to buy Finish tabs and we would be fine.
My mother called me weeks later saying that six of her tenants complained that their dishwasher was broken and she had already replaced one (two of the dishwashers were less than two years old). I told her to just gift them all a tub of tabs from Costco which worked.