Yeah many do leave, but they always return. My family left and then returned. I left now and plan to return, so do many of my friends and relatives.
Lebanese christians have survived in Lebanon for 1500 years and will survive for 1500 more years.
I frequently travel to a specific region of Mexico and often encounter the same Lebanese Christian man on my flights. He's expressed that same thoughts as you. It's sad that Lebanon was on the verge of greatness when Islam reared its ugly head.