Scientists must keep up to date with the latest research. Engineers must be familiar with knowledge that has already proved to be reliable and effective. If you are doing science, you can afford to be narrow and specialized. If you are doing engineering, you need a broad understanding of all the factors that affect the product you are designing. Scientists don't have to be licensed because they are chiefly accountable to other scientists.
Engineers do have to be licensed because they are chiefly accountable to the public.
An undergraduate science education prepares students to continue their studies. An undergraduate engineering education prepares students to enter the workforce immediately after completing their studies. Universities award computer science degrees, and they normally expect their computer science students to obtain software development jobs in which they will immediately begin solving real-world problems. Only a small fraction of computer science undergraduates go on to graduate school or research environments in which they are advancing the state of knowledge about software or computers. This puts computer science students into a technological no-man's land.