Can Using a Dumber Phone Cure 'Brain Rot'?

I need my phone to write and read Signal / Matrix messages and to use MFA. Unfortunately, dumb phones are generally too dumb for these requirements.

Perhaps an iq100 phone? Punkt is kinda close.

I feel like, in a day to day sense, my phone is more useful for chat and email than phoning people. I think a minimum phone that suited me would be closer to a pager.

The ideal smart phone for me would be an old BlackBerry.. physical keyboard and everything