Well the dishwasher I grew up with (branded Hotpoint, but essentially a Bosch) was the absolute BOL model and it only had three cycles:
1. Prewash
2. Super Wash 65º
3. Normal Wash 65º
The only difference between the two wash cycles was that Super Wash did 2 prewashes and Normal did 1 prewash. Both cycles then did a main wash at 65 ºC (150 ºF), purge, two full rinses (final rinse was 65C/150F) followed by a heated dry.
There was no way to reduce the wash or rinse temp and no way to turn off the heated dry. We used to fill the dispenser full of powder (which contained phosphate). Results were excellent and the dishwasher never smelled.
Now, my parents have a modern Bosch that defaults to the eco cycle every time it is switched on, unless you select a high-temp cycle, which they don't bother to do. Every time I go to their house, the dishwasher is disgusting. The filter is absolutely full of really thick grease. As well as only ever using the low temp eco cycle, it could be that they are using poor detergent tablets, which they stockpile and they may get old and damp. I have used modern Bosch dishwashers and mine have always remained pristine. But I use good detergent and high temps.
Their washing machine always used to be pristine too, with regular boil washes. Now, it's a disgusting, smelly, mouldy mess. They now wash exclusively at low temps.
So, at least in some cases, I'd say it's down to how the machine is (mis)used.