The arguments for using Optional (or its equivalents in other languages) as an alternative to bare nulls are covered in a recent article, The worst mistake of computer science. It quotes Tony Hoare, the inventor of the null reference, saying that null was a "billion-dollar mistake":
I call it my billion-dollar mistake... At that time, I was designing the first comprehensive type system for references in an object-oriented language. My goal was to ensure that all use of references should be absolutely safe, with checking performed automatically by the compiler. But I couldn’t resist the temptation to put in a null reference, simply because it was so easy to implement. This has led to innumerable errors, vulnerabilities, and system crashes, which have probably caused a billion dollars of pain and damage in the last forty years.