Passkeys and Modern Authentication

One day Authy for desktop was deprecated and all of a sudden I was forced to always have my smartphone with me, which I was struggling to replace with a dumbphone. To this day, I have no way out of owning an smartphone for this very reason

I assume you were using Authy desktop for TOTP? You don't need a smartphone for storing TOTP seeds or generating TOTP codes.

Are there many sites that only support Authy's push authentication and nothing else?

Indeed, but I have like 40 different cloud providers, social networks and SaaS' which would be a pain to migrate

No, not really, it's about migrating/restoring every single 2FA key would be extremely inconvenient

Do one a day :-)

TOTP should just be a (typically base32) secret string; I don't know if Authy allows exporting that though (and if not, that only underscores the point of this article).

I just use a simple shell script with dmenu/xclip/oathtool:

  #!/bin/zsh

  typeset -A opt=(
      Docker ABC
      GitHub DEF
      # ...
  )
  k=$(print -l ${(ko)opt} | dmenu -i)
  [[ $k != "" ]] && oathtool --totp --base32 $opt[$k] | xclip -rmlastnl

It's worth doing specifically because you can't be sure twilio won't do a second rug pull for mobile

I understand, but 40 doesn't sound too bad. When I moved from gmail to my custom domain, I had more than that to migrate. I just did it one at a time over a few months.

Same when I got my Yubikeys: I gradually moved the OTP seeds to them, wasn't that painful.

Ente Auth or Bitwarden?