As others have noted, many people have done centuries on straight bars. But drop bars are clearly more common in long distance endeavors because they offer varied hand positions and are more aerodynamic. If you don't like drop bars, it may be that you've never been properly fitted for them to feel comfortable; bars that are even 1cm too far away can cause shoulder and neck pain.

A compromise of sorts that I've been using recently is a flat bar with forward pointing stubs about shoulder-width apart. Some people call them inner bar ends and they kind of resemble aerobars. The flat bars, which these days are quite wide, give me control on technical terrain, while the inner bar ends give me an alternate handlebar position that is akin to riding the hoods of a drop bar and much more aerodynamic.

Here's a short video demonstrating the bars.