User pay formerly-public-infrastructure is what I identified as libertarian. Would you also advocate for residents of high crime areas to pay more taxes for police coverage?

"User pay" is typically associated with regressive per-use taxes. It's perfectly compatible with socialism to ensure the cost of the road system is applied to only automobile users in a progressive manner. Relatedly, Finland moving violation fines are not a fixed fee and are proportional to income: https://nri.today/wealthy-speedsters-beware-finlands-million... Stop thinking "cars=default", they are not.

Legally criminal actions are violations against the state, which is why a prosecutor decides whether to file charges and does not need the consent of the victim to do so. We already have what you suggest with civil law and private security.

It's pure pedantry to distinguish between "user pay" and "progressive fees" based on usage. You're advocating for private payments on public infrastructure, it doesn't make it socialism just because it's infrastructure you disapprove of.