They could, but you have to remember that these first & second gen machines did not have much in the way of detergent dispensers so that meant mostly one main wash followed by the after rinse or two. GE & Hotpoint did have dispensers and a prewash or rinse, but no drain that ground up food waste like later dishwashers did. The Bakelite impellers were not as sharp as the metal ones so they did not throw water as forcefully. No prewash or rinse meant tubs were not adequately heated up for the wash. These machines were not meant to scrub, but to wash off fresh soil and not heavy soil because they did not dispose of solid particles too well. This GE, for example, did not pause to let soil settle before the drain valve opened for the pump out because the main motor ran the timer and so the main motor had to keep running all through the cycle. The machine that GE came out with in 1957 was a great improvement over this one. Speaking from decades later, we can see how things improved, but then, what you saw was mostly what was available. There was one Westinghouse with a metal impeller. That combined with the guaranteed 140F water heating which extended the wash to close to an hour chipped away at soil, but the drain pump was small and did not move much more than water.
There were several machines in this generation that used a powerful pump instead of an impeller: KA & of course, Waste King, then less powerful pumps like Youngstown with an indirect spray system, the James and the Frigidaire spin spray tube.
