Should I blame someone unvaxed getting severe COVID-19, a well known and highly contagious disease with a free vax that greatly reduces the chance of severe infection? Absolutely.
COVID is particularly unique in its long ICU stays. Even for other conditions which could be blamed on poor patient decisions, 4 - 6 weeks in the ICU, and needing vents or ECMO, is not typical or widespread.
In the car analogy, we still have perfect biomarker tracking to determine exactly who, when and how long someone was infected and who exactly they infected. Perfect information. Obviously we don't have perfect information to hold people accountable, so we end up with tragedy of the commons. We need to protect the commons and the best option we have is through vaccination and limited access to the commons for those who refuse it.