I mostly ride a streetbike because I make a 500 mile trip (there, around, and back) every couple of weeks to an area that often gets gridlocked, or close to it, for easily 50 miles. On my bike, I can cut through it, making the long leg of my trip 3+1/2 hours instead of 3, but well ahead of the 4+1/2 it would be in a car in those conditions.
Also, as someone before me mentioned - focus. I'm so focused on the bike. It's almost like I'm prescient when riding, I'm just totally in tune with the traffic and I'm almost never surprised by what other drivers on the road do. When I drive my truck instead, I get distracted from driving by every little thing after a while, it's like I just dgaf and it's not a good space to be in.
(Not looking forward to the rainy season, when I do give up the bike - given that you're invisible on the best day on a bike, cover car windshields and windows with water, mist, make tires more slick, and it's too dangerous, not to mention uncomfortable... and my visibility is greatly reduced, too, so I can't keep myself above the flow of traffic, which makes my mental radar less reliable. Nope.)