What do you mean?In terms of "play anywhere". Let's say I have a rig and a laptop. The laptop isn't powerful enough to run RE7 well. However, if Steam can do PC-to-PC streaming, I can at least stream the game to the laptop from the rig.
XB1/PC PlayAnywhere is a deal that you buy the digital version of the game and can play on PC (Win10 Store) and XB1.
Steam well you can only play on Steam (PC).