Thanks.
I would reverse the modemmanager being set to “manually installed”, except… I don’t know what it means. I don’t know how it got set to be manually installed - or I don’t recall how that happened - and I don’t know how to reverse that.
output of /etc/apt/sources.list:
deb https://repo.pureos.net/pureos byzantium main
deb https://repo.pureos.net/pureos byzantium-updates main
deb https://repo.pureos.net/pureos byzantium-security main
# deb http://us.debian.org/debian bullseye-backports main
# deb https://repo.pureos.net/pureos octarine main