REMOVE REL ATTRIBUTE ADDED BY GUTENBERG, GUTENBERG automatically add rel attribute to the Anchor tag.

Please add the below code in your theme functions.php

//remove rel="noopener noreferrer" added in anchor tag
//below will remove from content and comments
//if rel is different just change rel in code
function remove_nofollow($string) {
	$string = str_ireplace(' rel="noopener noreferrer"', '', $string);
	return $string;
}
add_filter('the_content', 'remove_nofollow');
add_filter('comment_text', 'remove_nofollow');

Please let me know if it works for you. If any issue I will fix my code.