Substantial amounts of files unprocessed

I am running into issues with the PHPDOC Parser freshly installed today from SVN whereas several files simply are not processed.

Example, the JSON export (same when I create instead of export), remains as such:

{
        "file": {
            "description": "",
            "long_description": "",
            "tags": []
        },
        "path": "wp-includes\/post.php",
        "root": "\/Users\/username\/DEV\/MAMP\/wp-vanilla\/wordpress"
    },
    {

Or,

{
        "file": {
            "description": "",
            "long_description": "",
            "tags": []
        },
        "path": "wp-includes\/kses.php",
        "root": "\/Users\/username\/DEV\/MAMP\/wp-vanilla\/wordpress"
    },

This is on a Mac with latest WP, Parser, PHP8
It does not matter if I export or create

Basically, good two thirds of the files are not processed.
Most of the functions (register_post_type, for example) are therefore just never documented.

What can be the issue?

Reproduce the issue using the export and create commands against the listed WordPress files, especially wp-includes/post.php and wp-includes/kses.php, on PHP 8. Then trace why these files produce empty descriptions, long descriptions, and tags; done means the missing files and functions, including register_post_type, are processed and documented.