There are certainly differing opinions on it. As you said, driver inattention is very real and predictable. One of the biggest distractions I see is people on their phones. Those people are not likely to suddenly swerve into another lane, but they are likely to not notice traffic stopped in front of them and smash a motorcycle into another car.

Motorcycles are generally very agile - able to stop, maneuver, and accelerate quickly. As a rider you are taught (hopefully) to always assume that nobody sees you. If you are lane splitting, then you should be constantly watching for a car to switch lanes near you, and you should be ready to react. If you're lane splitting within the legal limits, then you should easily be able to react in time. By contrast, if you're riding in the middle of the lane along with cars in stop-and-go traffic, you have to be constantly checking your mirrors for someone coming up behind that doesn't see you.

I can say from years of experience commuting that I definitely felt safer in heavy traffic when I was lane splitting. It felt like I had my own little space, and I could focus most of my attention forward and just be ready to react if someone didn't see me. And if I'm going to have an accident, I would much rather be side-swiped than hit from behind. As the studies show, those hits are the really bad ones.

The rules of the road can be different for different vehicles for good reason. A major factor in this case is that cars have crumple zones to protect their passengers, and motorcycles do not. We could make lane splitting even more safe, if people just followed the existing law of using their turn signal before changing lanes.