While this is hardly an unknown fact amongst HN readers, a lot of people get very surprised when told about this.I've seen some of my colleagues going to private mode to browse something not work related, and when I explain that tbis won't help at all, they are almost shocked.

I am shocked, shocked to find that non-work related browsing is going on here!

I’m wondering if the new Brave browser’s Tor-based private mode makes a difference.

Many companies have systems circumventing https via additional certificates—effectively a man in the middle attack.

you mean everyone doesn't just use their phones for browsing non-work related things?

They do- most of them connected to the company's WiFi :)

But company doesn't know who has phone with given MAC address, while computers MACs are probably assigned to employee.

I'm sure I could trace it back to most people with high level of accuracy, as it's a small company.

It does if you have to log into the captive portal to use the wifi.

As someone who actually works on the IT-side of this, your statement is technically correct but my experience suggests a vanishingly-small number of employers actually monitor this data in any rigorous way. The only time I've ever seen an org reviewing web logs was in response to a specific formal HR complaint.