Pharmaceuticals would be devastated. While there are externalities that need to be solved around our production of drugs, the patent system is a good thing overall for them.
No one spends $1 billion to make a drug if anyone can copy it simply.
Additionally there are international problems related to abolishing patents.
Ease of copying. It takes some effort to reverse engineer a car, and things like manufacturing processes are difficult to ascertain by just looking at the final product. In contrast, many pharmaceuticals are relatively simple to copy and manufacture once you know the chemical composition of a product.
If you prefer you can think of software. However software is protected by Copyright quite sufficiently so doesn't come up when talking about patents (well in this way).
No one spends $1 billion to make a drug if anyone can copy it simply.
Additionally there are international problems related to abolishing patents.