I wasn't comparing healthcare to roads. I was commenting about how silly people sound when they say "it isn't free, taxes fund it".

Also, speed limits can be comparable to turnpike's, the interstates are rarely "blocked" unless you mean congested, which is a different issue and one that more road at that location would actually make worse. Construction costs are comparable to turnpike construction and maintenance costs and are slow because, unlike a turnpike it's most visible and most delaying in areas like cities where you can't move cars to a shoulder, something that isn't an issue for turnpikes..