Kind of true, but potentially also untrue. If that TV is running a crappy WiFi chip running an older WiFi standard on the same channel, it'll end up performing worse or not playing as nice with other clients during those bursts of buffering. That'll potentially be seen by other clients as little bursts of jitter.

That's true of any client with older and crappier WiFi chips though, but TVs are such a race to the bottom when it comes to performance in so many other things.