You say the morally correct thing, but being a Managed Identity Provider is gonna cost loads of money and they really have no business incentive to do this, in

You say the morally correct thing, but being a Managed Identity Provider is gonna cost loads of money and they really have no business incentive to do this, in fact it may be negative for some of their KPIs like the no. of sign ups they have on their site. The best course of action would have been for you to de-couple your Identity Provider from your account completely, I have done that over a course of a few months. I have de-coupled myself from Google Sign in on my most frequented sites, using Email + a Password manager + 2FA wherever its supported. though I have also have even used Apple's sign in for some apps