Like everything in life it's about balance, using too much foss software and hardware could put you in much more risk, while using proprietary software won't give you the control or privacy you want. Once again foss software is great, but it is not perfect and should not be treated as such.

There is no completely free software, even if you take out the Intel ME (which is a very bad idea as it'll leave you super vulnerable) The Intel chip will never be open source or FOSS at a hardware level. Even RISC-5 being open still has trust issues. Unless you setup a chip fab you're at the helm of someone. And as the closed source hardware runs the open source software, is it really free?

Honestly briar would be my pick in an ideal world, you don't need an internet connection, just Bluetooth. Sure it has short range but its the starting point for decentralized messaging

We live dangerously around here >:)

Me when I run sudo pacman -Syu