My apologies.
Apparently, I didn't clearly express my thoughts, as you've definitely misunderstood the processes and ideas I was attempting to describe.
I'll preface my attempt to express myself more clearly by reiterating that data on or traversing company owned property must be available to the company and/or its designees, even if that data is of a personal nature, as long as the there is a legitimate business need to inspect such data.
That said, I am not suggesting (nor am I sure why anyone would imagine that it's desirable or, in a large organization, even feasible) the decryption, capture and storage of every packet traversing such a network.
Rather, I'm merely pointing out that the owner of private property has the right to inspect such data. Even more, in certain circumstances (I'll address those below), an organization must do so to identify potential threats/incursions/data thefts and take appropriate action to mitigate or prevent such activity.
The circumstances under which this may be required include identifying potential compromise attempts (already widely done via IPS/deep packet inspection systems), malware payloads, data exfiltration and a variety of other threats.
I'm not claiming (or even implying) that all traffic should be reconstructed and manually reviewed.
That said, automated tools can (and should) be used to identify potential threats and network traffic tagged as such should be reviewed by the network/security personnel specifically designated and authorized to perform such activities.
I'd add that usage of corporate resources should be restricted to activities specifically related to the business of the organization, on devices that are owned and managed by that organization.
Other activities should be explicitly disallowed by policy and non-company owned devices should be barred from access to the internal network.
Which is why I specifically highlighted the use of "guest" networks in my initial comment[0]. That network to be used by external users as well as the personal devices of internal users for non-company business.
I do not advocate (unless the threat model requires it) ubuquitous surveillance of users. And all users should be informed of the policies and mechanisms in place that might trigger review of network data, as well as the potential repercussions of policy and/or legal violations.
When such reviews are triggered, any data collected around such potential threats/policy violations needs to be appropriately safeguarded, not only to protect the privacy of users, but also to protect the integrity of any investigation to be performed.
Again, we're talking about internal networks and systems wholly owned by the organization, and any device not in that set should be barred from connectivity to the internal network and forced to use the "guest" network.
As I also mentioned in my initial post[0], external cloud-based infrastructure is not in scope here, but is also an important topic that deserves an entire discussion itself. And Internet-facing applications accessed by external parties (e.g., customers) are also not in scope here. I am specifically referring to internal corporate users on company-owned devices.
As for bad actors and/or those who might "be blackmailed or simply ordered by the company to do unethical things, or ordered to grant access to someone who will do unethical things," organizational policies and the law should govern the consequences of such actions.
Until we have general AI[1] that can perform such tasks, we'll just have to use humans and (with appropriate policies/controls) trust them to do their jobs. When they don't, just as it's always been, there are consequences (including discipline, termination and civil/criminal legal action) for such bad behavior.
I hope I've been able to more clearly express myself this time.
[0] https://news.ycombinator.com/item?id=30575249
[1] https://en.wikipedia.org/wiki/Artificial_general_intelligenc...
Edit: Cleaned up some prose, clarified some arguments.