PHP7 came with many new features and changes. However, none of them were specifically for REST or web services. In fact, REST does not have any direct relation with language constructs. This is because REST is an architecture, while a language is there to provide constructs for implementation. So, does that mean PHP7 has some construct or feature which can make this implementation better? Yes and no. It depends on what we mean by implementation.
If we mean just getting a request and returning a response then No, there is no such specific feature. But, any RESTful Web Service is related to an entity, and an entity can have its own logic. So to provide RESTful Web Service for that entity, we need to write that logic as well. For this purpose, we will need to write more PHP code than just getting a request and returning a response. So to keep the code simple...
