The same reason you aren't. The same reason PGP has been around for 25 years and only a miniscule fraction of people ever encrypt their email.
I.e., it's because none of this privacy technology is built-in as the default into our communications infrastructure. Therefore, for the average person (and even for privacy-conscious techies), it is inconvenient and difficult, and you have to convince the party you're talking with to also install and configure something that is inconvenient and difficult for them.
I'm convinced that the question of why end-to-end crypto isn't the default is a political one; i.e., there is pressure not to do it.
Shifting people onto E2E encrypted VOIP as we move off analog phone lines would be far easier than moving peoples existing email to PGP. Much like how it was pretty seemless for WhatsApp to turn it on.
Email is a special case because of the various semantics like searching and federated clients.
It's really not that hard. Mumble works quite well in TCP mode, via Tor onion service. That gives you end-to-end encryption plus some anonymity. Except for the voiceprint issue, anyway. And you get cellular-level sound quality. Latency isn't problematic if you run in press-to-transmit mode.
Politicians and their staff should not be ignorant; they ought be very acutely aware of the risks and that they are a target, and ought be highly motivated to fix this for themselves by securing their own systems.
