I've read about this on another newspaper this morning and I think that it could be a great advertising if used properly: although Bill Gates came out in the past with anti-Bitcoin speech, now Microsoft trusts it enough to use its blockchain. (And yes, I know, they've said it in the past too, cryptocurrency is not blockchain and they do like the blockchain tech).
Bill Gates isn't involved with Microsoft much these days, he's just a major shareholder now. And even if he criticized Bitcoin in the past, he isn't a raging nocoiner/buttcoiner who devotes too much time to fightning Bitcoin. Maybe he doesn't even know that Microsoft released this product, or simple doesn't care.
As for the tool itself, if the concerns of privacy advocates are real, then it's really not something we should cheer for, just because it uses Bitcoin.
Privacy advocates are always going to be wary about Microsofts because like Facebook, it's often what they do in the past and this is why according to Christopher Allen is that the salient result may simply be accelerated data collection which is most likely what will happen. The two companies are going to be associated with breaching privacy. The noblest cause they can do may still shred doubts to people particularly those who are concern about their privacy.