Yes, even ARM and other System-On-A-Chip hardwares can all be unsmarted. Most of them are easy, you just need to trick it into updating to the correct version and then using built in commands to give you more access: most use Linux such as the TizenOS which is standard on Samsung TVs or the GoogleTV OS which is a modified Android 3.0 or 3.2 version. Some of the more difficult ones can still be forced to dump their OS onto memory cards because their system on a chip has a pin for injecting code natively.

There is no TV that cannot be unsmarted.