So basically NETWATCH has one BIG ass secret: they are NOT able to do their one and most important job which is to secure and repair the BLACKWALL. The why to this is complicated, the Blackwall was created during the 2040s (also known as Cyberpunk RED, the TTRPG and official prequel) by Alt + SoulKiller victims of Arasaka that had their conciousness forcibly uploaded into the Net + Transcendental AIs (AIs from before the DataKrash that evolved beyond human comprehension after the fall of the OldNet). The help Netwatch provided to this creation was only but minuscule.
All this to say: Netwatch does not have the capabilites to manipulate the Blackwall in any capacity. Still they are the "least" evil corpo for a reason, they are highly devoted and have a big sense of Duty to their mission of keeping the Blackwall alive and standing. To fix these issue they desperately look for means to get it, which includes capturing and manipulating powerful AIs.
The BLACKWALL is basically the ONLY thing protecting humanity against the ROGUE AIs from beyond the wall. I dont think its possible to completely understand this plot point without playing Phantom Liberty honestly, the DLC explains and showcase this masterfully.
The Rogue AIs are extremely powerful and destructive AIs that originated from the DataKrash, when Rache Bartmoss freed the R.A.B.I.D.S. viruses into the OldNet. Among many other things inside the Net there where Military-Grade AIs created solely for War (most probably used during the Fourth Corporate War and the South American war) that HEAVILY mutated after being corrupter by the viruses. These Rogue AIs are extremely violent and want to either enslave or destroy humanity, as to them we are nothing more than pests and parasites.
This means that the The Fall of the Blackwall is an apocalypse level event that puts the ENTIRE Humanity and the planet itself in danger of being destroyed. It would literally mean the end of the world as we know it.
NETWATCH is extremely aware of this immediate danger, because as the Voodoo Boys say: the Fall is very very near, its just a matter or time. People KEEP poking fingers at the fall, CORPORATIONs (like Militech with Project CYNOSURE) keep messing with this shit. The Wall will not hold forever and is near to reach its LIMIT. Even Slider, an ex-Voodoo Boy in the DLC, is SCARED SHITLESS the second he sees the smallest trace of Blackwall stuff.
HOW DOES THIS RELATES TO JOHNNY?
Because both NETWATCH and the VOODOO BOYS desperately want to contact ALT, and they want to use Johnny as BAIT in order to bring her back from Beyond the Wall. The VOODOO BOYS want to make a deal with her in order to have a powerful AI protecting them when the Fall happens. And finally NETWATCH wants primarily CAPTURE her, she is one of the core creators of the Wall and they NEED someone that can manipulate and FIX the damned thing.
NETWATCH wanted Johnny specifically for this very purpose. The exact same reason the VOODOO BOYS also wanted Johnny.
As per usual with Johnny fucking Silverhand, he wants to believe he is important when he is nothing more than a pawn in a game that surpasses him in every single way imaginable.
WHAT DOES YORINOBU GETS FROM THIS?
To destroy ARASAKA from the inside, this was always his plan. To give SOULKILLER, the most important weapon ARASAKA has at their disposal, to a rival Corpo.
Its extremely implied that during a birthday when Yorinobu was young Saburo explicitly told him what his fate was going to be: to become a SECOND body of him, exactly the same way WE become a second body of Johnny. As shown in THE DEVIL ending, Saburo uses the RELIC on Yorinobu. This is the beginning of his hatred for Arasaka, and the reason why he abandoned the family and become a NOMAD of the STEEL DRAGONS.
"IF BOMB ISNT ENOUGH, YOU BECOME BOMB" is one of his last lines.
Ive seen a lot of people not paying attention to the story and its getting on my nerves. The story is complex and has many underlying layers, its one of the reasons why i love this game so much.