They don't have to be though there is grippy paint you can get, clearly they haven't bothered here though
There is a balance though.
Part of any race is skill and bike handling... and road cycling is a sport that has always taken place on open roads!
Ofc dont want things to be unnecessarily dangerous.
But take out all hazards is impossible even over a 30km stretch of road in a built up place...
only way to make everything perfect is to just have every race on a turbo-trainer aha. Or can just measure everyones lactate levels, V02 max and watts/kg that morning and decide results off that. Aha.