A number of sites use email, which can be a pain (though on iPhone, toggling between apps is easy). More generally, 2FA can be a pain - especially when integrating between an app and my iPhone (especially PingID, Authenticator and Outlook - but that's a special circle of hell for corporate implementation of tech!)Put it in your Google or Apple Wallet. The app is indeed an inconvenient way to use these cards, but fortunately all smartphones, however basic, have wallet functionality.
Do the same with e-tickets (and if you think you might double-use one by accident, simply delete them from there after use).
This just goes back to people not using smartphones as they are designed to be used and then moaning about them being a faff to use in the incorrect manner. Spend a few minutes learning to use one as it is intended and you will find it to be a smooth and convenient experience.
Also why would you need a laptop for 2 Factor Authentication? It is usually a text message to your phone. What sort of 2FA are you using that runs on a laptop?
Text message 2FA is very old school and increasingly regarded as insecure.