Since it's irreplaceable I don't think it's enough. Games could easily hit 25+GB (larger textures and more cinematics at higher res) and I'm not willing to delete/re-install games all the time in the future. Even if you can already start the game while installing I'm still wondering whether they mean play any section of the game you want or not (using old save data).
However you can just plug-in an external Hard-Drive but then the question is what specs should it have in order to get the same loading speeds and performance. It's a bit of a drag to have so many different devices underneath your TV so I think they should have put in at least 1TB or made it possible to replace it yourself.
Stories unfolded with my home made rap songs. Feel free to listen here with lyrics: https://youtu.be/vyT9PbK5_T0
