Hi,
To clarify: Are you trying to use the Block Element as a page-hero section alternative to Header Element?
If yes, {{post_title}}
is not the way to go as it will only work on Header Element.
To work on Block Elements (Gutenberg Editor), you’ll have to find a way to make a block display the post title.
One way to do that is through making your own shortcode.
Here’s an example of a PHP snippet displaying post title w/ [post_title] shortcode.
add_shortcode( 'post_title', function() {
ob_start();
// Start your PHP below
echo get_the_title(get_the_id());
// End your PHP above
return ob_get_clean();
} );
Other alternatives may require installing additional plugins that add dynamic text blocks to Gutenberg Editor.