Yeah, definitely having well water, especially unsoftened and untreated, is going to have pretty notable effects on the water pressure in that there's probably some buildup in the pipes. Silicates and mineral build up are the main reason that dishwashers lose effectiveness. You can absolutely have a 40 year old machine that works well and cleans every dish in every load on soft, treated water, or a 3 year old machine that is absolutely fucking unusable no matter how many times you repeat the load.

Some dishwashers will also have a little salt compartment which is used to recharge the ion-exchange water softeners that are built into those dishwashers. This is more common in Europe, but I've used multiple dishwashers in the US and Canada that did have them as well. This may be something to check for, just in case yours has it.