You can tell me anything what's bitcoin worst enemy is...
Mine is, government!
I think altcoin is friend of bitcoin becuase altcoin is a way to trade some coins in bitcoin so thats why the value of bitcoin totally increasing but the enemy of bitcoin is goverment becuase many goverment banning the bitcoin.
I agree with you because of many altcoins the value of bitcoin is became strong and high and yes many goverment ban the bitcoin bevuase they did not control the bitcoin so thats why they illegalized the bitcoin in their country.