Hi
Ok so going back to the top of the thread:
The real question is: Are modified sine waves an issue with *modern* TV power supplies?
The issue isn't that they are switchers. The issue is the power factor correction. If you have a PFC supply (as most modern gear is), it will work to level out the mess that a rectifier based load puts on the mains. That circuit *expects* to see a sine wave. When you give it something weird it does something weird. In this case weird is not good. The current leveling pulses happen at the wrong time and both the inverter and the load get a bit bothered. The PFC heats up and the inverter is not as efficient as it should be (= it gets hotter as well). No, it will not burst into flames. Yes, it will have a shorter life that it otherwise would have had.
Bob