Hi there!

The omitted type is intended, to avoid the duplication between the type in the argument list and the PHPdoc (this can only get out-of-sync). According to the specification of phpDocumentor (and the related "draft" PSR), the type can be omitted in @param:

With the @param tag it is possible to document the Type and the intent of a single argument of a function or method. When provided it MAY contain a Type to indicate what is expected.

This is actually an open bug in phpstorm.

Although the codebase is not consistent on this point (that's another topic), I'm 👎 for the reason given by Wouter: this is a PHPStorm bug, not a Symfony one. Thanks for proposing, hope to see you in another contrib