Your exposure to medieval art must be very limited. I have seen some very magnificent pieces of medieval art personally. And paintings are a small part of what falls under "medieval art". Include those in the category, please.
And there is another element to consider, which is the purpose of the art. Medieval art was not concerned so much with realism, but with the symbolic.
I wonder: do you think Byzantine icons "suck"? I suspect you do.
Do you just want to generalize, or do you want to provide a counterexample? Fine either way.
Stop being an obnoxious pest.
What would be the point? Any example given will be met with some snarky and ignorant remark. Veit Stoss's Krakow triptych? Gentile da Fabriano's "Adoration of the Magi"? Byzantine art, like Monreale Cathedral? The Christ Pantocrator icon from St. Catherine's Monastery? Romanesque and gothic cathedrals? Ornate illuminated manuscripts? Shall I continue? You don't have to like medieval art, but claiming it "sucks" is not only generalizing (your very accusation in this thread), but it is boorish and ignorant. You've already gotten more "discussion" out of this topic than you deserve.
So, go troll somewhere else.
I checked your first example. It's from 1423, well outside the time period 500-1300. If you have valid examples, including the other works you mentioned above, please provide dates. I'm a little tired of doing that for people.
Adoration of the Magi, 1423. https://en.wikipedia.org/wiki/Adoration_of_the_Magi_(Gentile...