A good first step would be to impose liability for engineers designing roads which predictably leads to the deaths of its users.

I imagine a road-building engineer would think twice before approving a road with an unsafe design speed if it could lead to them being stripped of their license, fined or even jailed.

Why blame anyone? A general rule: If you want someone to blame, look in the mirror.

Because if you want to solve a problem you first have to identify it. That's step 1, before anything else. There's no virtue in being ignorant, especially not purposefully so.

Identifying a problem and blame are different things. The first facilitates problem solving, the second interferes with it. Look up blame-free post-mortems of problems in the IT world, for example.

Blaming is similar to a victim perspective, IMHO: 'I'm innocent (most important) and injured; the other person is guilty; therefore I can take out my frustration, etc. on them - I can do to them whatever I want.' It often is more about satisfying anger, protection from shame and other consequences, and is a distraction from problem solving. And those blamed, as here on HN, are often the people who are most socially acceptable to blame - whoever is unpopular and vulnerable in the current crowd.

In this case, people driving cars and riding bicycles are in a system that yields problematic results. How can we improve that system? Talking about blame

The roads are working as intended. If you want to change them you need political control. Will be tough seeing as most people do not want them changed.