For the future, I want to ride to Alaska. I want to ride to the southern tip of Baja Mexico. I want to ride to the east coast. If I ditched my bike, then none of these would occur. On a bike some of them probably will over the next few years.
So, I think that it comes down to a question of motivation. Is the bike just for getting yourself from point A to point B? If so, then a car will likely be more pleasant and safer. If the point is the trip, then it seems that is likely to work out better on a bike. There are, of course, many many steps between these two extremes, but most of my trips seem to generally be sorted into one broad bucket or the other which makes the selection of vehicle self-evident... So, why is exploring on a bike so engrossing?
On a bike, you smell everything! That lovely pine aroma... road kill... pesticides... storage ponds with anaerobic decomposition. The smell of summer in the dessert right after a rain storm! That's worth a trip, right there.
You can't tune out, which I find that I do in a car. It's not a matter of staring out into space until you get there, it's the dozens of little things that you have to watch out for. This constant concentration requires emersions in the now. It is the zen state of "I'd rather not die just yet".
You can wave at nearly anyone and get a return wave. Almost everyone feels they have a conversation opening with "nice bike". You have a 180 degree view by just swiveling your head. You get the reductionism enforced by limited cargo space. I can wander around for weeks with only 1 change of clothes, and it's really not all that bad, and that's with a fairly voluminous first aid kit, and tool kit.
So, I've found that trips on the bike are the bee's knees, and bees have two sets of knees, so that means that they kick twice as much ass as you would normally find on a single person. That's a lot of ass to kick!