The eye is broadband and the desired light is bright, so it takes a very high power density to jam it. LIDAR receivers are very narrowband and the desired light is fairly dim, so jamming it will be quite easy. Modulation does not help when the light detector is saturated.
To keep the detector saturated for any period of time you would need to have aim that's a little too perfect. Besides, my central point was that there are lots of vulnerabilities in existing cars and they're still driven.
In case you decide to test your theory about lasers and human eyes, please don't use someone else as a test subject.
I think it can be done without aiming, assuming the light detector uses a wide angle lens. You just have to illuminate the scene observed by the LIDAR with a few watts per square meter of laser light. That's doable today, and easy in the future.
Besides, using the right modulation would make LIDAR as hard to jam as would be needed.