Disable Core Gutenberg Blocks

disable-core-blocks.php

add_filter('allowed_block_types', 'ca_allowed_block_types');

function ca_allowed_block_types($allowed_blocks)
{
    $allowed_blocks = [];
    $block_types = WP_Block_Type_Registry::get_instance()->get_all_registered();
    $blocks = array_keys($block_types);

    foreach ($blocks as $block => $block_name) {

        if (strpos($block_name, 'core') !== 0) {
            $allowed_blocks[] = $block_name;
        }

        // leave this block in as taking it out removes some editor formatting
        if ($block_name == 'core/paragraph') {
            $allowed_blocks[] = $block_name;
        }
    }
    // var_dump($allowed_blocks);
    // die();
    return $allowed_blocks;
}