If JSON wizard only has Path Chooser and has "path" set and "mandatory" set like this:

{
                    "name": "Path",
                    "type": "PathChooser",
                    "trDisplayName": "Path:",
                    "mandatory": true,
                    "data":
                    {
                        "kind": "directory",
                        "basePath": "%{InitialPath}",
                        "path": "%{InitialPath}"
                    }
}

then it is not possible to click Next unless clicking on Browse and back, which is not needed if the default path suits for the user. Should be able to click Next if the default path exists and is ok to the user.

You can test this by modifying existing cpp wizard in share/qtcreator/templates/wizards/classes/cpp/wizard.json. Just remove all fields except PathChooser and try to add Class in Code editor.