Connected cars are very useful for end-users. I use my car's app to remote-start, lock/unlock, check diagnostics, etc all the time. If for some reason my car was stolen, I could track it remotely. If I got in a crash and was unresponsive, the car calls for help. I want all those features.
The problem isn't being connected, any more than your smartphone being connected is a problem. The problem is control. Who has control of what, when? It should be us in control of what data is used, when, for what purposes. If companies won't voluntarily put control in our hands, we need the government to mandate it.
I agree with the ideal end state being control over your data, but the hack described in this report points out that privacy isn't the only problem.
You're trusting a central service with the ability to perform those actions on your behalf; if that service has any vulnerabilities, it doesn't matter how much control you have over your data.