Cat. 7 network from main house to annex underground

I'm out of here.

It's probably for the best, because otherwise you would have already read that the OP has confirmed that in his case fiber optic does not solve the lightning strike problem and that equipotential bonding is not necessary because everything is connected to the same house connection anyway. You don't have to play missionary, but if you recommend something to an unsuspecting user, you should be able to justify it.

The fact is: in his situation, fiber optic makes no sense technically, financially, or physically.

Isn't the beautiful thing about a forum that you get presented with different approaches and can then decide what the best way is for yourself with all the pros and cons? There simply usually isn't just one right way!

There simply isn’t (usually) one right way!

According to some members here, there apparently is, namely their own.

not the one right way!

Since not a single user in four pages of the thread could explain why the OP should reasonably use fiber optics, I dare to doubt it in this particular case.

throw out some plausible reasons, then other solutions can be discussed.

Simply just because you can.

That's why I had written "sinnvollerweise".