A Christian is anywho who believes in Christ. The largest Christian denomination, Catholicism, does not believe in a young Earth. You trying to paint all Christians as fundamentalists is the same as people trying to generalize all black people based on what they see on rap videos. Small population, big generalization. So yea...
Worst analogy ever...
No bro, regardless of what the Catholic church says... Christianity is predicated on the bible. Jesus himself said that the old testament was God's word, and it was the truth. You can be the largest denomination of Christianity all day, but you're not really Christian if you're flat out saying that Jesus was wrong.
It's semantics though. It's all how you define the word. I'm just saying that LITERAL Christianity is believing in young earth, bottom line and end of story. If you don't believe that, you're conceding that you don't believe everything in the bible. Jesus didn't say anything about it being okay to cherry pick.