So, if you would, help me out with the 'why' part

It eliminates a single point of failure, can be used to bypass censorship, and allow for community support/engagement in a way that is harder to track and suppress (in that there's no 'central' hub and you have to go after nodes individually. From an opsec point of view, you're still broadcasting a signal that someone in range can pick up). Obviously it requires many devices to make a good mesh work, but short of DOSing every channel or just blowing out the signal space, it's gonna be hard to take that down.

I see it as something like tor or i2p, not something for general use at the moment, but definitely has good uses.

This is an example of what an Internet service providers network might look like.

They use many different types of specialized computers and devices to connect your house (one of the grey rectangles) to the greater Internet (the yellow rectangle in the middle).

One person is arguing that instead of the Internet service provider owning all of the red green and blue computers... Other people would own them. And maybe the red computer for your neighborhood would physically be inside your neighbor's house, instead of in a small building or box on the side of the road somewhere nearby.

Functionally, it's the same Internet, regardless of who owns the red box. Though theoretically, it could be less safe to give random people, potentially bad actors, access to the physical computer that is the red box, because they could do something malicious with it. But the point is, if the technology is working correctly, it doesn't matter who owns it, everyone's private home networks (everything downstream of your grey rectangle), are kept separate.

Just like normal Internet, you can't print on your neighbor's network printer, just because you both have the same ISP and share the same red computer upstream somewhere. The red computer won't let it happen.

Does that make sense?

Now, the concern of the other guy, it seems, comes from not understanding this. Not understanding that the red computers are specially configured by the ISP, or whoever owns it, to keep the grey rectangles separate.

What he might be thinking, is something similar to sharing your Wi-Fi password. Or maybe running an Ethernet cable over the fence and plugging your neighbor's router into your router. Things start to get complicated here, so I'll gloss over a lot of things, but essentially... Your home router is not configured like the red computers are. So all of your neighbors data would be going through your home network, and you could very likely see what he's doing, and he could potentially see what you're doing (provided there's no double NAT, but even then I'm not sure, maybe).

Basically, if two or more neighbors want to share Internet, but don't know how to do it safely, then they can expose their private network activity to each other and open each other up to a decent amount of risk.

The solution, is to configure your router in a similar way to the red computers. It's complicated, but not that difficult in practice. You could Google VLANs to get an idea of what would need to be done. Honestly you'd need more than that, some good firewall rules, and more things that I'm not qualified to comment on. I'm not a networkologist. But it can be done.

The debate/argument stems from a basic misunderstanding of how these systems work. Or perhaps they both understand how they work, but the guy who doesn't want to do it is just worried about his neighbors being untrustworthy with the hardware being in their house, worried they'll be nefarious, but he's just bad at communicating that idea to the other guy.

At any rate, it doesn't matter who owns the red computers or the green or blue, if they're configured correctly, you're safe. Unless you don't trust whoever owns the computers 🤷‍♂️

Hopefully that makes sense! Let me know if you have any questions!

There's not really too much of a debate, just a lack of deep understanding of how the infrastructure works under the hood.

The other person (rightly) doesn't want to share their local network (what's behind your wifi router) with their neighbors. My only point was that, much like current ISPs, you don't share any networking with your neighbors. The only thing remotely close to 'shared' would be the individual uplinks (your ISP connection) from each residence to the (shared) networking gear of the ISP.

A local ISP and a Telco aren't (shouldn't) going to be handling the base networking layer any differently. They'll all have individual connections between them and subscribers, and the only way that I could get into your network is to setup services and configure either side to talk to the service on the other.

To actually ELI5 (which I am exceptionally bad at with actual 5yos), Alice and Bob both get their toys from Charles (Telco ISP) who charges a lot of money, and doesn't treat them well when they try to use the toys they got. Dan comes a long and works with Ed and Fred to set up a local toy store and try to treat customers better. Bob (irmadlad) is concerned that the new local toy store means he'll have to share the toys he bought with Alice, not realizing neither store makes you share your toys.