Limiting image uploads

I used the snippet like this:

function limit_file_uploads( $form ) {
    
    if( $form['name'] != "advert" ) {
        return $form;
    }

    foreach( $form["field"] as $key => $field ) {
        if( $field["name"] != "gallery" ) {
            continue;
        }
        
        $form["field"][$key]["validator"] = array();
        

        // Set minimum and maximum file upload size.
        // Note. this is a limit for an individual file, not whole gallery field.
        $form["field"][$key]["validator"][] = array(
            "name" => "upload_size",
            "params" => array( 
                "min" => null,     // minimum file size
                "max" => "200KB"     // maximum file size
            )
        );
    }

    return $form;
}

I added an image on an ad that was 5.70MB — it allowed that. When I view the image in the ad itself, it shows an image with an intrinsic size of 5312×2988 pixels at 878×494 pixels. If I look in the Media Library, there’s an image with that intrinsic size that’s 6MB. It did not stick to my 200KB max as in the snippet.

NOTE: There are 2 other images there, too, even though I removed them from the ad before publishing. Shouldn’t it delete images that weren’t used in the final ad? Can that be revised so it happens?