spoilers:end of spoilers
There's also that he's not the Sorcerer Supreme yet. He might not be on authority to look out for magic abuses yet.
One thing is for sure though. Someone needs to train Wanda and she needs therapy. The people of Westview need therapy.
The show all along dealt with depression and grief in a very real and human way. It just did not do that with the ending. Marvel handwaves actual treatment too much. And treats it's citizens like fodder.
Sure they never forgive Wanda and she didn't mean to do it. But people still have to live with what happened here.
For there to be any lesson learned, Wanda needs treatment and education to help prevent this from happening again. Doctor Strange can maybe do that.