Someone said being a good person was more important than believing in God; why did he get a thumbs down?

Because just being a good person doesn't earn religious leaders a good living. You have to remember that religion exists to maintain the power, wealth and prestige of its leaders - if you don't patronise them, the business collapses. So, they don't care how you behave, as long as you go to church, pay your money, vote how they want you to vote and so on.