Are we speakin of adding the content after you already have Civ 5? Yeah it's worth it.
But GOTY Edition? Steam and 2K can flush that borked out piece of garbage. Cause DX11 has NEVER worked and I've done every "fix" that both companies tried to peddle on me as the way to get it to work. Now I don't even care if I ever play another Civ game as long as I live. Absolutely ruined the game for me. My Bro can play DX11 on the original Civ 5 on his system. GOTY is trash. Stay far far far away from it.