Glad you're here to tell us about it, hope you're otherwise well.
"Let you have it"? Nope. You did everything right IMHO. Reducing as much speed as physically possible until the moment of impact was your best option and you didn't do anything stupid like "laying it down" or other crap that some still believe is the right course of action - more reasons to discuss things like this and dispel those old myths.
In the advanced rider training I took a month or so back this exact scenario was part of the training. Often there's nothing a rider can do to avoid an accident - there's no "out". There's no time to stop fully. Too fast to simply swerve and avoid. So, the best course of action is to accept you're going to hit, but scrub as much speed as is physically possible right up to the moment of impact. Obviously hitting at a lower speed is better than a higher speed, your case in point.
So, the learning experience here? Practice threshold braking regularly - in your situation you walked away. In a similar situation from someone who didn't know or practice emergency braking, it would have been much worse.
In going over this incident in my head i realized that i started in the left block position but by end of the accident i hit his passenger fender, obviously i drifted right. Perhaps somewhere in the back of my mind i was praying he would see me and stop so i had room to get around in front of him.
Food for thought.
Lost a few layers of skin, tweaked my slipped discs again slightly, replaced some gear, had to regain some lost pride, i'll take it. Certainly if i had been ripping it i would have been launched into the stratosphere over his hood.
/shrug