It seems like a widespread problem but it's really not. It's actually dozens or even hundreds of individual problems that all cause the same symptoms in different areas. Unless you live on the same block with another poster, the problems are almost always caused by different things. The cable network is vulnerable to a lot of RF interference that doesn't affect fiber optic or copper baseband (DSL) networks. That RF interference is probably what Cox is referring to when they talk about "bad connections". Cable is also a lot more complex than those other networks so it needs constant maintenance to keep it running. I see major upstream packet loss due to noise ingress about every 4 to 6 weeks. Sometimes I call the tech, other times I wait for a neighbor to call a tech. The tech always fixes it, but it always comes back. Like I said, constant maintenance.
Oversubscription and congestion are also problems, but like I said that's an individual problem in each neighborhood even though it causes the same type of problem for everyone.
Unfortunately there's nothing Cox can do to to fix the "widespread problem" because to completely fix it would require fixing all of those hundreds of individual problems on the network. All you can do is schedule a tech to come out and hope they can identify whatever individual problem is occurring in your neighborhood. Then when the problem comes back, call for a tech again. Repeat this process until Cox finally runs fiber to your home, whenever that may be.