I absolutely get your point but I think at least some of that is on you, or on those services. There are supposed to be safeguards that remove (or at least miti

I absolutely get your point but I think at least some of that is on you, or on those services. There are supposed to be safeguards that remove (or at least mitigate) the risk of denial of service caused by loss of the secondary device. One-time-use codes or some other method for emergency access are common ones I can think of.