exclude categories from WP home page

hmph.php

in functions.php file
<?php

add_filter( 'pre_get_posts', function ( $query ) {
if ( $query->is_home() && $query->is_main_query() ) {
$example_term = get_term_by( 'name', 'featured', 'category' );
$example_term_2 = get_term_by( 'name', 'Featured Post', 'category' );
$example_term_3 = get_term_by( 'name', '1,000 Stories', 'category' );
$example_term_4 = get_term_by( 'name', '1,000 Stories Spotlight', 'category' );
$query->set( 'category__not_in', $example_term->term_id, $example_term_2->term_id, $example_term_3->term_id, $example_term_4->term_id );
}
});

?>

in index.php file

<?php 
    if ( have_posts() ) {
    while ( have_posts() ) {
        the_post();
        x_get_view( 'ethos', 'content', get_post_format() );
    }
}
?>

That's not a valid post loop, and a mixture of 2 syntax's. This is what a standard post loop should look like:

if ( have_posts() ) {
    while ( have_posts() ) {
        the_post();
        // do things
    }
}

notes:

• if: endif; and while: endwhile; are shorthand
• if() {} and while () {} are not shorthand
• putting the_post(); on the same line as the while loop is bad practice, but it appears everywhere. A single line should do a single thing, makes it easier to debug
• you've got stray ?><?php tags in there too, save yourself the time and don't bother typing them out, it does nothing

Thanks! Fixed that, but posts are still not being excluded.