Comparing Bitcoin and altcoins is like equating gold and silver. Regardless of how silver is refined, its worth will not be greater than gold. There are some altcoins that have adopted additional features such as low transaction fees and more security, but they have not been able to overtake Bitcoin. Institutions and even nations recognises it mpore than any other crytocurrency. Bitcoin is also widely adopted and less volitile.  It is not impossible for Bitcoin to loss its number one position but it will be very difficult.