I wouldn't make it so I would have to flip a 5G switch and activate the nanomachines or graphene/phosphorene matrices to kill them.
Absolutely not!
Why not? Because then they could still escape if they left the range of the 5G towers.
No no no...
We can't give hope to the slaves. We can't suggest that if they isolate themselves from the control structures that they could possibly survive.
Instead, I would make it so that the kill-switch would automatically activate if they leave the 5G tower area, or whatever remote that would constantly send out a signal ping to them.
That would be a much better plan.
It would guarantee that any of the ambitious sheep who dare leave the "permitted" areas would immediately drop dead. Then, the dumb-ass sheep would immediately associate certain areas as danger areas, not suitable for survival. They'd blame it on the "virus" or "climate change" just like we'd tell them to.
Effectively, this guarantees subservience to big cities and government dependence. Sustainable living will be exterminated entirely. We can't have any rats flee the nest.
Everyone will own nothing and be happy, right?
There are some hold-ups though. Like airplane passengers and pilots getting out of range of the towers, or not being able to transition between signals. Hikers and sportsmen who spend too much time out in parks and nature as well would be vulnerable to low levels of reception.
Frequently dropping signal would eventually result in death, even if the losses are relatively brief, so it's not like there won't be some loss of the livestock in the name of "progress."
I'd consider those glitches in the system, but the fear it generates would nonetheless serve the ultimate purpose in keeping people where they are instead of gallivanting around MY world without MY permission.
This all reminds me of the Fallout games, where slave collars activate when they get too far from the remote and their heads explode.
If you're gonna enslave humanity, this would be the way to do it.
Why? What is the underlying motivation?
Well, most think it's just a culling they want, and that's true in part.
But I figure it's less a culling and more a curating. They need to reduce the number of genetic "mistakes" in the gene pool so that "humanity can evolve".
In reality, this is all just setting the stage of the Devil's goal of exterminating humanity, seeing them as God's mistake in Creation; that they are entities with God's authority going about ruining things.
Think of Satan as if he were the head butler and the Master of the house let some jackasses live there. The head butler disagrees with the rabble-rousers that he now has to take orders from and clean up after.
The butler's primary motivation is to frame and/or trick us into getting kicked out. Meanwhile, some of the rabble-rousers are dumb enough to fall for the Devil's tricks, up to and including killing 90% of the guests.
Then the butler comes up to the Master and says "See! Your experiment failed! These things aren't worthy to live in your house, now they are killing one another, so get rid of them."