I want to say T-Mobile is requiring VoLTE (I recall discussion about this because it effectively mean the Nokia N900 cannot be used on T-Mobile or its NVMOs any

I want to say T-Mobile is requiring VoLTE (I recall discussion about this because it effectively mean the Nokia N900 cannot be used on T-Mobile or its NVMOs anymore). I will comment that the Pinephone works with VoLTE on many carriers (I know it works with T-Mobile), and Purism is actively working on VoLTE for the Librem 5 (I remember seeing them actively working it a few months ago, so I guess they have it working now?).