They still have uses
The biggest abuse of the patent system by far is in computers, especially software. When US software patents were first allowed in the 1970s, nobody knew how fast the industry would grow, or that a typical program would use dozens of "patentable" ideas. I remember in college when the field was young there were a few "great ideas" in computer science, and everybody knew who invented them. These days there are so many patentable ideas that nobody even knows where they came from or even when you inadvertently use them.
But there are industries which couldn't survive without patents. In the pharmaceutical industry, it typically costs very little to actually produce a drug. By far most of the money goes into R&D and testing. Since the patent starts when the drug molecule is first synthesized, by the time the drug passes the FDA there are only a few years left on the patent. If there were no patents, nobody would ever spend the money to create a new drug.
