They tried to do the same thing as they did with Scarlett Witch in Multiverse of Madness. He worked you get his love back and turned into the villain by trying to absorb the powers of others. The only difference is that Supreme Strange didn't really have much of a villain arc and it just seemed wrong to have him go so far back, trying to get Christine back after he had just come to terms with it. Scarlett Witch just made more sense.
What do you think?