WP 6.5 evaluating function

HI there – In previous WP versions, the code block that follows returned the content of a post with my slight customizations when using the shortcode within a post or template. I have several similar functions that I use, but this is the simplest to share for sake of the example.

function generate_custom_post($customtext) {
global $post;
if ( '' == $customtext ) {
$customtext = get_the_content('');
$customtext = apply_filters('the_content', $customtext);
}
return $customtext;
}

add_shortcode( 'custom_post', 'generate_custom_post' );

In WP 6.5, when using the shortcode within a post it simply returns the string “Array”. I have disabled all plugins and activated the default theme and the problem persists. Is there something about the way 6.5 would evaluate this that’s different? Thanks.