i have one question..
in 2011 bitcoins per 50,000 to 500,000 we spent for nothing, just pranking and stuff...
if one person kept 50,000 bitcoins in his account from 2011 up till now,
would the bitcoins still be valid for transactions?
yes! there is no expiration. it is still valid no matter how long you have them, as long as you still have the private key.