About Ballistiscs and Murder holes upgrades in University

So When I see the description of Ballistics in the tech tree in-game, it doesn’t say Skirmishers are applied but when I see the description of upgrades of Skirmisher it says accuracy upgrade available in University. With examples like this I reallize that the descriptions/explanation in the tech tree is not accurate and/or enough. And I have a couple of things that I want to know of.

A wiki suggests that Murder hole doesn’t include Bombard Tower and I see no such descriptions, is it true? And what about Town Center and other defensive structures such as Donjon, Crepost and the Malay upgraded arrows firing Dock(or Port)?

And in the description Ballistics excludes defensive towers and I want to know about that too.

Finally if you see the description of Castle at the last part of the upgrades; it says attack, range (castle). That’s not correct is it? Cuz, I see no such things with my eyes wide open.

Not every units/buildings are affected to some techs

This should inform you :

Thank you. I will look into it and might ask you again if i have further questions.