That's like saying if I punch someone because of a legal dispute, the law is to blame.

Civil contract disputes don't obligate you to commit crimes in the process of trying to make things right.

The power inverters were *not their property*. Remotely accessing them, without authorization and with the intent of disabling them, is a textbook CFAA felony.

Their 'right' to do that was probably somewhere in unreadable ALL CAPS on a small piece of paper at the bottom of the shipping box that the end user never got.

Fuck 'em. Isolate your local net from the world and only let through devices you trust. Plenty of ways to do that, even at low expense. But you will have to make the effort or pay someone else to do it.

Not to mention the slight complication of the entity is not in your jurisdiction and subject to your laws.

You buy a device from an intermediary and it phones home to a foreign jurisdiction. That sucks but I'm not sure what recourse you can realistically expect.

The US is plenty capable of making any entity they want fall under their jurisdiction.