I think it is possible for bitcoin to become a global currency because of how fast bitcoin is growing. You can see bitcoin reaching almost 6k while 2 weeks ago it was 3k. This is why i think bitcoin will even reach higher numbers and can easily be the second paying method instead of usd.
Price don't mean a thing in this many don't want to use this cuz price is let say unstable. Cuz of this many will think twice between this, if price someday becomes stable then sure it will be possitive outcome for global usage.