Yes, exactly. The panel's control system is connected to the Internet and there's an app that an attacker could take advantage of to interfere with critical infrastructure at an inopportune time.

If you are doing grid-scale installation, surely you would want your own control system (perhaps also on your own network, separated from the general internet), precisely in order to protect the grid.

There’s always the issue that it might be hard to find competent people that can implement a control network isolated from the internet if it has an internet connection by default.