The blessing had to do with bearing Christ and raising him.
Now, as an adult he had to be 'about His Father's business'.
Now, where does 'rather' mean that. It means a preference or choice of one thing over another.
I'd rather have ice cream then spinach.
The 'rather' here is very clear, Mary is not the way of blessing, the word of God is.
I just explained that. You read Greek? I do.