My ex-husband suffered from these his entire life. He worked retail as his day job and was a musician the rest of the time
He was on his feet all day.
Here is how I stopped the pain cycle. You cannot stop the way the nail grows into and around the toe, you have to work with what is there.
When he would get out of the
shower, about once a week or so, he would immediately present his feet to me for maintenance. With tweezers I would very gently pull out the dead layers of skin that build up between the nail bed (cuticle) and the nail edge. Not all but just what was starting to flake away. This allowed a thicker barrier to build up between the flesh and the nail without trying to change the fact that the nail was going to be there. This removed the pressure while allowing the callus to protect the skin. We always trimmed his nails straight, never allowing a point or top of the nail to press into the area. To cut the nail away and remove the thick layer of skin that could form a callus just seemed to keep creating the problem over and over again. His mother did this to him for years! He was almost always in constant pain. I sure hope his current wife learned the technique!
Hope this is clear, if not I can try to draw a diagram