The most important aspect here is remote connectivity. Software without remote connectivity may be less correctable, but it is also resistant towards tampering from unwanted directions. With network connectivity the device basically becomes impossible to fully control. In fact, admin control shifts from you, the owner, to someone else on the other side of the planet, unless you want to take a hammer to it.
These issue need vigorous debate. 1. Do we even want every device to become "smart"?, and 2. should smart devices be designed with 24x7 network connectivity requirements?