This again makes me wonder how Johnny H managed to acquire weapons/abilities of such game-changing power that never existed in the original time line.
The original timeline of TOS was rife with asymmetric threats - it was actually extremely rare for Kirk to face a threat on his tech level! With so many superior foes of the Federation around, beggars can be choosers. Assuming John Harrison is a beggar, rather than one of the big boys to start with.
The trailer would have us believe that Earth or the Federation feels protected in this timeline. Was this ever the case in TOS? There were many threats capable of reaching and hurting Earth; by the time of the movies, they actually did. Is the game really being changed?