I've used dial up via a cheap modem to a Cisco 2500 as recently as a few years ago for OOB console access. It's not gold plated but still works fine More recen

I've used dial up via a cheap modem to a Cisco 2500 as recently as a few years ago for OOB console access. It's not gold plated but still works fine More recently though it's all been on ethernet handoff either via the DC or a local provider