His prior dishwasher videos rescued my parents' 30-ish year old dishwasher -- one they had previously been advised to avoid replacing as long as possible, as modern units don't have the same construction quality.

Following his cleaning instructions and, subsequently, his usage advice, did the trick.

Regarding the latter, notably adding the recommended prewash dose of detergent in addition to the main dose, and running the kitchen sink's hot tap until the water is fully hot before starting the dishwasher. Here in the US with our lower power capacity, resulting in dishwasher heating elements being restricted to lower power to avoid circuit breaker trips, when the dishwasher is correctly connected to the hot water line (typically, of the kitchen sink), doing this results in a hotter prewash and often also wash.

This all really does make a substantial difference.

Take the time to watch his dishwasher videos. If you struggle at all with the performance of yours, you won't regret doing so.