Why Raspbian is 32-bit
This is because the old Raspberry Pis are still supported (which is good) but have a 32-bit CPU, which means they couldn’t run a 64-bit OS, however 64-bit CPUs can run a 32-bit OS. So, it kind of makes sense to make the OS 32-bit for everyone by default. However, there are some performance benefits of using a 64-bit OS on a 64-bit CPU, to leverage the capabilities of the CPU.
the 64-bit CPU capabilities thanks to the new 64-bit Linux kernel which can give us a performance boost in some situations.
It seems that if your hardware is 64-bit, you will actually get a performance boost when using the 64-bit version of the Raspbian operating system compared to using the 32-bit version of the Raspbian operating system.
Additionally, by having the 64-bit operating system, you will be able to use the latest version of the Jami application.
There is a post in these forums where the Jami developers have written (in French) that provides the instructions on how to install Jami on an always-on computer (in your case, your Raspberry Pi) without the GUI. The link to the instructions (written in French) is: