I'd say you have to view it differently. You said, "So, for the sake of helping me, please just assume that my assessments of certain designs are accurate, and that they are undeniably awful, and had the designer(s) attempted to use their design once they would have realize this -- and that it's not just me." So, you'll have to enlarge your context on this. You can, perhaps, try to empathize with people not exposed to the notion of good design, or people that can't conceive of it, or live impoverished enough inner lives to have no concern for it at all. You should realize that you yourself certainly have equally large and glaring blind spots invisible to you, and sympathize with the human condition.
If you continue to view it as simply indefensible, you'll never solve anything. If you feel strongly about it, perhaps you can start teaching design, or raising awareness about design. But, in the end, you have this restricted circle of concern, this bad design attacks you personally and you cannot forgive it.
This piece seems insightful about this point:
https://www.concordmonitor.com/Bertrand-Russell-conquest-of-...
“I am persuaded that those who quite sincerely attribute their sorrows to their views about the universe are putting the cart before the horse: the truth is that they are unhappy for some reason of which they are not aware, and this unhappiness leads them to dwell upon the less agreeable characteristics of the world in which they live.”
“Gradually I learned to be indifferent to myself and my deficiencies; I came to center my attention increasingly upon external objects: the state of the world, various branches of knowledge, individuals for whom I felt affection.” - Obviously, you've already directed your attention outwardly, but in this case, I think you need to widen your perspective and circle of concern until these issues seem small. You get tunnel vision on them.
“The secret of happiness is this: let your interests be as wide as possible, and let your reactions to things and persons that interest you be as far as possible friendly rather than hostile.”
“The wise man thinks about his troubles only when there is some purpose in doing so; at other times he thinks about other things, or, if it is night, about nothing at all. . . . It is amazing how much both happiness and efficiency can be increased by the cultivation of an orderly mind, which thinks about a matter adequately at the right time rather than inadequately at all times.”
Anyway, my $0.02