The perspectives and interests of NIST and the things that a service provider has has to worry about with respect to their customer/user experience are not necessarily aligned.
Customer: "What do you mean two factor app? I thought the code was supposed to come to my phone?"
Support: "It did, but we no longer support SMS two factor authentication."
Customer: "But I had no problems when the code came to my phone."
Support: "Yes, but NIST recommends that we don't use SMS 2FA"
Customer: "What's NIST? I'm finding this very frustrating, I need to get into my account."
Customer: "What do you mean two factor app? I thought the code was supposed to come to my phone?"
Support: "It did, but we no longer support SMS two factor authentication."
Customer: "But I had no problems when the code came to my phone."
Support: "Yes, but NIST recommends that we don't use SMS 2FA"
Customer: "What's NIST? I'm finding this very frustrating, I need to get into my account."