I registered boolean by register_meta(), to use it in my Gutenberg Plugin Sidebar, I added default value to it true:

register_meta( 'post', '_thefuturmeta_post_title_visibility', array(
    'show_in_rest' => [
        'schema' => [
            'type'    => 'boolean',
            'default' => true,
        ]
    ],
    'type' => 'boolean',
    'single' => true,
    'sanitize_callback' => 'sanitize_text_field',
    'auth_callback' => function() {
        return current_user_can( 'edit_posts' );
    }
) );

So after registering I can see its value in my console, then by my Gutenberg Sidebar I added ToggleControl and can change this value, and everything's working perfect.

But I can't get my value properly in my theme:

$visibility_title = get_post_meta( get_the_ID(), '_thefuturmeta_post_title_visibility', true );
var_dump($visibility_title);

var_dump() will always show boolean(true), if I change default value in get_post_meta to false like this:

$visibility_title = get_post_meta( get_the_ID(), '_thefuturmeta_post_title_visibility', false );

I will get bool(false) even if in my sidebar plugin I have true, but If I switch in my sidebar plugin to false and save and again switch to true, after this $visibility_title will be showing always right values depending on ToggleControl.

What am I doing wrong? I'm sure I have problem exactly here:

$visibility_title = get_post_meta( get_the_ID(), '_thefuturmeta_post_title_visibility', true );

But I can't understand what's wrong.

Can you help me, please?