Why does Tomcat still need an empty beans.xml for registering CDI? How to make Tomcat register CDI without empty beans.xml

Question

In a simple JSF 2.2 project using Mojarra. There is a managed bean:

@RequestScoped
@Named(value="myHello")
public Hello {
    private String name = "test";
    public void setName(String name) {
        this.name = name;
    }
    public String getName() {
        return name;
    }
}

and this managed bean is used in a jsf with placeholder #{myHello.name}. In order to make the CDI work, weld 3.1.3 Final (CDI 2.0 implementation) is added as dependency

The compiled war is deployed to a Tomcat 8 servlet container.

Unexpected result: the JSF can be displayed fluently, but #{myHello.name} didn't ouput test as expected but nothing

The ogirinal solution was add an empty beans.xml to WEB-INF directory according to the answer in How to install and use CDI on Tomcat?, and it indeed can work out this problem.

But being that the note in Weld 3.1.3 Final specification:

The beans.xml file is no longer required for CDI enablement as of CDI 1.1. CDI is automatically enabled for archives which don’t contain beans.xml but contain one or more bean classes with a bean defining annotation

An empty beans.xml would not be necessary any more.

Question:

• Why is an empty beans.xml still compulsory?
• How to make the placeholder #{myHello.name} work properly without an empty beans.xml?