For a really simple camera I use an old DLink. No subscription, no cloud storage. It records to an SD card in the camera. It is connected to the WiFi if I want notifications or to view it remotely. If I just want recording it does not have to be connected to anything except power. Really simple, pretty cheap. They can be powered from an outlet or battery. Not very smart, ie, it can send many false alarms.
All of this is mostly about privacy vs security.
I also have a Ring camera that is several years old now. The downside to it is the delay between someone coming in frame and how long it takes to respond. The old ad about answering the door remotely is not always true. 10sec to 1 minute delay. But, it has been great on alerts, especially when we are on vacation. It has no local recording and has a small annual subscription. And, yes, Ring has always had their "Neighborhood" thing. It allows sharing video with others in your area. I opted out simply because it was annoying to me. Ring can access any of the cloud storage.
Yes, any of the WiFi systems can be hacked or disabled, just as cell phone service can be locally disabled. Just takes the right equipment. If that level of security is important, get a good security company to give you some advice. At work I had the really good stuff, but, it costs a lot and much of it will be wired with a 24/7 monitor service. I also had a dedicated line which is not cheap. It was a government system, so, yeah, they had access to everything
Yes, most cases the company has access to your video and can release it. Yes, your phone can be tracked almost anywhere if the right people want to. Same with your computer usage on the internet. Basically, anything that goes over cell service or internet is accessible. Yes, there are laws about it, but, that really doesn't matter much unless you are going to court.
You have to judge if the security the cameras provide is worth the possible loss of privacy.
The 'good' part is that no one really monitors your stuff unless they find a reason to. Heck, maybe posting in a gun forum is enough to get you monitored more closely
