I use third party identity providers for all webservices I offer. Not that many because I am not web dev. People love it but I wouldn't use it myself. Of course the identity provider could extract information about the services you use, I wouldn't like that for most platforms to be honest not for the net as a whole.

Account creation sucks, but I prefer it to letting an ID provider know about it. Although I would trust real third party ones like auth0 more than Facebook or Apple, even if they have a more focused business model.