I have the large size Luminoodle on a 65" TV and it is great. Makes watching TV in a dark room easier on the eyes and guests seem to like it.
A bias light that is color keyed to what’s on the screen might be better, but you can pretty much only get that with a TV that has it built in.
You can get 6 foot RGB strips at Walmart for $5, but they’re not long enough for a 65" and the new wears off of the color change feature pretty quickly.
Not all flat screens have USB ports.