If you look at the engineering workstation segment, there are companies with hundreds or thousands of seats pooling FlexLM licenses of very expensive software, namely for microelectronics design.

Those seats are typically RedHat or CentOS. If you look up revenues for Cadence, Mentor and Synopsys, most of it is EDA software licensing (remainder is mostly IP and training.)

Not prime time news, but not pocket change either.

The enterprise is relatively easy to sell software to GNU/Linux users, because what gets sold is actually training, support and consulting.

All things that non-technical consumers don't care to pay a dime for, but they usually buy shrink-wrapped software, even if on digital form.

I believed back then, and still now, that money is to be made with experts & service. Seems to work very well for companies like RedHat and IBM.

True, but it also boosts the non-traditional Linux desktop. Something like the Chromebook would be a flop 15 years ago.

They only see a window manager taking care of Chrome instances, with ChromeOS specific APIs.

Google can release a Chromebook without any access to Crouton, replaced the Linux kernel by something else, and no USA school buying Chromebooks would notice.

Same applies to Android, specially after the Android 7 locked on linking to private shared objects.