Terrified by practice exam results; perspective requested.

So I'm reasonably far along in my preparation for the CISSP, or so I thought until I did this practice exam.
https://www.concise-courses.com/test-yourself/cissp/

From the Cybrary videos and other sources I was under the impression that many of the questions here were far more technically detailed than I should reasonably expect to see on the CISSP exam. Can anyone who has taken the exam or seen enough of these questions on this forum give me some perspective on this? I'm happy to delve deeply enough to know packet header numbers and messages & IRC/FTP/TELNET commands, I just didnt expect to see them on the CISSP. Thoughts?

As an aside I'm in furious agreement that this practice exam covers necessary basics for a security professional. My question is purely focused on what one should reasonably expect to contend with on the exam in terms of technical details such as packet fields etc.

Regards
Scott