Except in terms of speed
Exploring isn't meant to mean zooming through communities as fast as you can. You can cover over 100km a day by bike, and truly experience the areas you're passing through.
safety
Probably safer than driving. People in cars make cycle touring unsafe, but you don't have to bike alongside them in many cases.
convenience
This is a matter of perspective. Some people, like myself, enjoy planning, gearing up, and executing the plan way more than "what's the easiest way to do this?".
comfort.
Debatable. I find sitting in a car for hours at a time to be excruciating. But I can sit on my bike and ride for 10+ hours at a time, and still want more. And if you're in traffic? Good luck.
If you are doing a proper cycle tour or bikepacking adventure, there's going to be a lot of opportunities to stop, visit local spots, eat, etc.
To me, a "road trip" is about the experience. Everything that comes after that is going to be about how you get to enjoy that experience. And I'd rather be doing it outside of a metal cage. I think most people who've experienced more than just driving would probably agree.