I am new here, so i hope it's ok to comment.
As an ex breeder, i agree with some of what is said. However, i also think we cannot expect someone to NOT breed just because their mare may be sub standard. Except for glaring faults that do affect their function and/or comfort, anyone should have the right to breed their own mare, no matter what others think of her. As long as they are willing to care for that foal. To breed to sell is a whole other matter and i would hope they would understand the limits of selling one.
But many wonderful horses have come from what others would determine substandard parents. And if a person just wants a baby from their favorite mare, I see no harm in it. But they should be prepared to assure that the offspring is well cared for!!!!