> Humans mess up mispainted lane lines also. Have seen many times where there were 2-3 conflicting lane lines painted and people just kinda drove where ever.

That's very true, I've seen it as well. I think the big difference is that humans have the context and experience to deal with those situations on the fly, making choices that a self driving systems just haven't matured enough to make; this is why I advocate for better alerting systems rather than anything that changes the trajectory of the car on its own.