Wait, I don't understand, but I want to.
Are you saying that the frame rate for the native signal we get from "providers" is ALWAYS less than the native frame rate of even a 120Hz TV?
And if you are watching Actual TV, they send at 1080i, so you are only getting 30 full frames per second in an interlaced format. So first field is the even lines, the next field is the odd lines at 60Hz.
Most BluRays are recorded at 25Hz, But as the LCD TV is all digital, it can refresh at any rate it feels like. So there is no 4:3 sync BS with adding in extra frames to match a fixed refresh rate like old TV's. No, the TV just changed is rate to a slower 25Hz to match the BluRay.
With the faster TV's you are paying for either it to re-paint the same image on the screen 2, 4 or 8 times more than it needs to, or the TV has to make up what it thinks are the frames between what is has NOW and what it thinks it will get 16ms from now for TV or 40ms for your BluRay.
Now an IPS pannel were once much slower than a TN or PVA, but the speeds have caught up. so the newer IPS and its iterations can now transition between 5ms to 11ms depending on the colour change extremes.
Back when LCD first came out, the transition times were in the 40-60ms range, and YES there were issues with ghosting. The marketing teams use this to sell you a feature that you will never really use.