My company recently took away text-message as a way to 2FA and wanted us to download their app. I told them (politely) that I had an authorization app already that I trusted because it was Open Source (Bitwarden) and could I use that instead of installing a corporate app on my device.

They said no.

Never install your work's corporate spyware on your own personal device. Rule #1. If they want me to install their shit, they can provide the phone for me to do it.