It's Adele, nobody can sell like her. /endthread
But in general, I'd say it's because of the different demographic. The people who buy Adele's albums a lot of the time are older and don't use streaming services, or prefer to have the CD. Beyoncé had everyone scrambling onto Tidal. Why are you comparing?
I don't know why Taylor sells how she does, I guess she appeals to the whole GP - people and their kids.