Stop Breaking TLS

I agree with the sentiment, but I think it's a pretty naive view of the issue. Companies will want all info they can in case some of their workers does something illegal-inappropiate to deflect the blame. That's a much more palpable risk than "local CA certificates being compromised or something like that.

And some of the arguments are just very easily dismissed. You don't want your employer to see you medical records? Why were you browsing them during work hours and using your employers' device in the first place?

I’m all for privacy of individuals, but work network is not a public internet either.

A solution is required to limit the network to work related activities and also inspect server communications for unusual patterns.

In one example someone’s phone was using the work WiFi to “accidentally” stream 20 GB of Netflix a day.

What's the security risk of someone streaming Netflix?

There are better ways to ensure people are getting their work done that don't involve spying on them in the name of "security".

Security 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.