I see, you are just another guy who lacks knowledge about this transfer market. Let me break this into three parts and you will understand why the scenario I put wasn't ridiculous but more realistic than yours.
First of all, where is this link shows we are prioritising striker and CB? So far, what we know is CB and attacker. And winger is in the category of attacker.
Second, Kessie only has 1 year left in his contract. This is common sense that he's going to cost around 25m-35m, signing a player who only has one year left in his contract with a dream to play for Man United is the easiest and most realistic ideal transfer. And if we use your logic about various media, lot of media already say that Sancho will cost so much cheaper this summer which common sense because Sancho will only have 2 years left in his contract.
Third, I can ask the same question. Have you forgotten who the owner is? What makes you think Kessie and Sancho combined will cost that much? In reality Sancho will cost cheaper than Haaland this summer, Kessie will cost cheaper than CB this summer. Buying those two is actually easier and cheaper than buying top class striker and CB. Knowing our owner, you should know which scenario they prefer.