Q.Does it hurt to stomp onion tops down prior to harvest
Does it hurt to stomp the onion tops down prior to harvest? Will this cause them to rot in winter? Does this cause any problems with onions for winter storage?

Stomping down the greens is done by many gardeners, mine own grandparents used this method.
It is best to allow the onion tops to die down naturally.
Here is a couple of links with more information.
https://www.gardeningknowhow.com/edible/vegetables/onion/harvesting-onions.htm
https://www.gardeningknowhow.com/edible/vegetables/onion/storing-onions.htm