1. Bing as a brand needs to maintain standards. It cannot keep on showing crypto ads as there are a lot of scams online and they cannot risk their brand image.

2.  Secondly, a lot of these ads capture user/consumer data online. With the new rules of GDPR in EU, it will be very strict on how and what the data captured will be used for. All users have the rights not to be tracked, or their personal information should not be used in any other illegal way. Unless these are clarified, it is probably best to take a precautionary stance.