Without btc alt coins would no longer exist, and all of tokens when converted to real currency undergo to btc. This makes btc become popular and continually increase its value. There's no doubt btc is the most strongest digital currency ever made by mankind:)
You are right and we all know that bitcoin is the first crypto currency made successful in the world. A lot of coins right now are just relying from bitcoin. Many people called bitcoin as mother of all currency because without bitcoin there would no currency at all.