Matthew 16:26 And what do you benefit if you gain the whole world but lose your own soul? Is anything worth more than your soul?
Not only is my life full now, it will be much fuller for eternity. Why
on earth would you settle for less? This is merely basic training.
Without Christ you can gain the whole world. With Him, you can gain the whole world, all the other worlds our Father has created, and an eternal non-corruptible body that never fails, to enjoy them with.
There is meaningful, and then there is meaningful, never ending.
If you are right and I am wrong, you and I have lived meaningful lives and then we rot away. No harm, no foul...
If you are wrong and I am right, you have lost everything but a forgetful vapor of existence in linear time, and I have gain everything, forever. Yay me...
John 1:12 says, “To all who did receive him [Jesus], who believed in his name, he gave the right to become children of God.”
Being a child of God is not for everyone. No one is forced to accept the gift of eternal life. Nothing arrogant about it. It's free and available to everyone. Those who never heard of Christ will be judged on the way they treated their fellow man. Those who refuse the gift of propitiation offed by God and His Son, will be judged at the White Throne Judgement.
Naive would be being so myopic that you don't even see the choice that has been offered you...