Yes these true 2.4 ghz radios are so cheap I am not sure why people stay with the proprietary factory radios, when you can buy a full featured radio for less.
Futaba and Spektrum hold a loyal following from years of quality and the fact of expensive gear was always part of the hobby. The cheaper prices for Txs are a relatively new thing, but few are going to trust a $6000 1/4 Fieseler Storch to a knock-off clone.
It makes little difference for our purposes since we're rarely far from the tank and if it lost control, there's not much trouble it can get into, so $8 Orange Rxs are fine. But there's no way I'm going to use a HK Tx with AC or boats where loss of signal means loss of model or possible damage to property.