The world is constantly in a state of termoil at this point in time, despite the many attempts by Silver in travelling to the past in order to fix it.
A previous version of the timeline saw the world conquered by the Eggman Empire, where everyone was said to be living in fear and choking on polluted air. This was changed after Silver travelled back to the present to aide the Resistance in combating the Eggman Empire. (StH: #8)
Silver returned to his time after the war to find the world in another dire situation, however; the Eggman Empire had vanished, but the rest of the world had become barren of any organic life, with only metallic plant life remaining, prompting Silver to return to the present yet again. (StH: #8)