That article has a cool evolving history of dishwasher design. And I'd be surprised if things weren't less diverse in the market, honestly. One important thing I would add is that Bosch is one of the most popular dishwasher manufacturers worldwide and their products are offered under multiple brandings. This and the fact that they all effectively function the same easily corroborates your findings, without making anything generic about it.

All I can tell you is at the end of the day, your Siemens is literally a Bosch manufactured unit.

They use a fair amount more energy, most wash motors of this vintage draw about 4 amps vs. modern units at 0.75-1.5 amp. The heater is resistive so it's about the same. The wash cycle for an older machine like this is going to be much shorter though, so the energy offset isn't nearly as much as you'd expect. It will definitely use a few extra gallons of water in a cycle, but again, not a massive increase but one that will add up over several years of ownership.

They will heat the water themselves, but hot water is expected to be supplied to it - the higher the inlet water temperature, the more effective and efficient the wash. Almost all digital controlled units will throw a fault if the inlet water temp is below 70° f.

Starting with it hot (and using your already heated water from the water heater) is much more efficient for the machine.

In actuality, Bosch absorbed Siemens home appliance division in 2015. Bosch units are a novel design compared to other manufacturers, nothing generic about it.