Is bitcoin a future proof currency?
We are now in the future yes,but we cannot predict what will happen 3 or 5 years from now maybe a new coin with revolutionary features that could over shadow what bitcoin is offering to it's users now..
I doubt that there will a new coin which can move or even collapse bitcoin with all it's commodity of users only during 3 years . Bitcoin is strong crypto currency which have so many users in the whole world.
By the way just keep believe in bitcoin and join to "playing"with bitcoin, you will found a feel that can give you a proof.
Something will replace Bitcoin and have its transactions used more than Bitcoin as well. I just don't think that it has arrived as of yet. Bitcoin is at a point where only nerds and a few other groups that know how to turn on a computer get to use it.
If some kind of Government decides on building a Cryptocurrency then releases it to the public then the userbase will be multiple times bigger than Bitcoin.