I wonder if there will be a way to connect to other platforms, like tuya/smartlife or even to "import" devices through Google home. 

In a way that one could set for example "if my + my wife phones disconnect from the network, run the turn off all lights on the Google home" 

Basically the main idea of Matter, that you are no longer Committed to control every device solely from its app but can go cross platforms, with apps like Google home or Alexa etc.