Avoid embedding YouTube videos and open them in a new window

How about this shortcode:

function alternative_youtube_embed_func( $atts ) {
    $a = shortcode_atts( array(
        'id' => 'ScMzIvxBSi4' // youtube video ID from video URL
    ), $atts);
    return '<a href="https://www.youtube.com/watch?v=' . $a["id"] . '" rel="noopener noreferrer" target="_blank"><img width="560" height="315" src="https://img.youtube.com/vi/' . $a["id"] . '/0.jpg" alt="link to youtube video" /></a>';
add_shortcode( 'alternative-youtube-embed', 'alternative_youtube_embed_func' );

Add a play-button overlay with CSS, and voilà.

Additional Info:
You might want to remove the embed blocks so users can’t use them, see here.