My older Netgear R6700 has three antennas and says it does simultaneous dual band 3x3 Tx/Rx. So it can transmit or receive three signals at once. Isn't that essentially what MU-MIMO is doing? Is the industry creating new terms as a marketing hype for something that had already existed for years? Just like they started using the terms Wifi 5 and Wifi 6 which simply refers to 802.11ac and 802.11ax respectively.