Is this washing machine drain hose too long/ installed wrong?
I would agree the extra loop will create increased resistance and possibly not pump as well.
I would shorten the hose if nothing else to reduce the back pressure on the pump.
I know my washer has a check valve at the exit of the pump so it should not let dirty water flow back but I would think eliminating any flow restrictions and a longer hose is a resistance to flow that if eliminated may solve your rinse issue.