Modern dishwasher machines are ridiculously efficient. On a normal automatic cycle, my machine will use between 3.4-6.4 gallons of water total. An average kitchen faucet is between 1.5-1.8 gallons / minute based on some spot checking of specs online. Which means it only takes running your faucet for 2-3 minutes before you're into the low side of the washing machine and just 4.5 minutes before you're using more than a fully loaded cycle in the washing machine would use. I recently had a month where we couldn't use the dishwasher and washed by hand every night. Our water usage for the month was noticeably higher for that month than it has been in any month before or since. It's really kind of crazy how good a modern dishwasher is.

Both views feel extreme to me. When I was single, sometimes I used the dishwasher, and sometimes I washed by hand. In either case I wasn't wasting water, because I didn't run the dishwasher until it was full, which was roughly biweekly.

When washing by hand, I did what you imply you do, which is use much, much less than bowlfulls of water for my meal. I get what parent is saying though, because of the numerous roommates I'd had while single, some of them would use gallons of water to wash a single meals worth of dishes, i.e. the plate, cutlery, and maybe a cup. Much more if they had cooked their meal instead of microwaved it