I got rid of my smartphone several years ago and haven't looked back. Whenever possible, I use SMS-based 2FA on my dumbphone (a LightPhone II). When an authenticator app is required, I just use KeePassXC on my GNU/Linux desktop computer. This is an open source password manager that also has the ability to generate the time-based passcodes associated with proprietary 2FA programs like Google or Microsoft Authenticator. Give it a try and see if it meets your needs. Good luck and happy hacking!