We are idiots who will bear the consequences of our own idiocy. The big issue with all transactions done under significant information asymmetry is moral hazard. The person performing the service has far less incentive to ensure a good outcome past the conclusion of the transaction than the person who lives with the outcome.

Applies doubly now that many health care interactions are transactional and you won't even see the same doctor again.

On a systemic level, the likely outcome is just that people who manage their health better will survive, while people who don't will die. Evolution in action. Managing your health means paying attention when something is wrong and seeking out the right specialist to fix it, while also discarding specialists who won't help you fix it.

Neither does collective responsibility, for the same reason, particularly in any sort of representative government. Or did you expect people to pause being idiots as soon as they stepped into the ballot box to choose the people they wanted to have collective responsibility?