Cameras inside the house get internet access, so intruders can't just walk off with your footage, but external camera feeds are fine to be stored locally.
That'd take very little skill to set up, prevents anyone from using those external connections to get at the rest of your network or abuse your internet connection,you don't have to worry about jammers, the police won't be accessing your feed whenever they feel like it, and Amazon won't be keeping detailed logs of everyone who comes to your door, how often you have company over, what your daily/weekly schedule is like, how often you get food delivered, what kinds of clothing you and your guests are wearing, how many children are in your home, how many pets, how often you go out on the weekends vs staying inside, how often you vacation and for how long, how many friends you have, how often you have non-amazon packages delivered, what kind of car you drive, etc
You can't build a system that's immune to every possible type of attack, but fortunately you don't have to. Most people will never catch a single "bad guy" with their camera set up, and will never have anyone mess with the system at all. That doesn't mean it's not a good idea to take a few simple steps to better protect yourself, your family, your packages, your network and your privacy. If you see value in having your surroundings captured on camera you can gain a lot of benefits for a small amount of effort by throwing your ring cameras in the trash and setting up a dedicated network for their replacements.
Typically the things on my home network that need to be isolated and/or revoked Internet access are not in physical proximity with one another, so using a separate switch for them means a lot more wiring. It is much simpler to just run devices to the nearest already existing switch and do the isolation in software. This also cuts down on the number of switches which means fewer points of failure.
For the crowd who can't isolate the cameras from the rest of their network and don't already have a bunch of networking equipment laying around though a dedicated network for the security cams is a easy solution that offers a lot of advantages over a ring cam.
"... but I think that's outside the relm of what most consumers can do."