There’s about a mile section that is only one lane near the little village of Kahakaloa. I ride my bike through there often, mostly to go get banana bread. When traffic gets messed up, I just go by them all with my bike. Normally not tons of traffic, but I could see that section becoming a mess if people from north of Lahaina were all going that way to get to Kahului. The rest of the road is just windy but I wouldn’t call it treacherous, or even dangerous for that matter. I’m sure people that may have been a bit panicked to get out were shooting through there faster than they should have. It’s normally 25 mph. But yes, the views are spectacular.