alt Hacker NewsSecurity takes many forms, including Availability.
Having branch offices with 100 Mbps (or less!) Internet connections is still common. I’ve worked tickets where the root cause of network problems such as dropped calls ended up being due to bandwidth constraints. Get enough users streaming Spotify and Netflix and it can get in the way of legitimate business needs.
Sure, there’s shaping/qos rules and dns blocking. But the point is that some networks are no place for personal consumption. If an employer wants to use a MITM box to enforce that, so be it.
I think that's a very loose interpretation of Availability in the CIA triad.
This looks a lot like using the MITM hammer to crack every nut.
If this is an actual concern, why not deny personal devices access to the network? Why not restrict the applications that can run on company devices? Or provide a separate connection for personal devices/browsing/streaming?
Why not treat them like people and actually talk to them about the potential impacts. Give people personal responsibility for what they do at work.