they can't lie, they could be open to be sued.I genuinly think so as well. I have noticed most big billion dollar companies won't just lie, so if they are saying it's selling well, it must be doing so.
I've also noticed it's got positive user scores, and the QoL features are good as well.
that's why m$ never gives number etc.. and according to them, they fix numbers for shareholders to suit them...