Disable User Social Profiles

Using the code snippet here, you can remove ALL of the social profiles from the user sections for ALL users. To remove select social profiles, only unset the ones that you do NOT want.

For MySpace and Wikipedia, this should do it.

/* Remove Yoast SEO Social Profiles From All Users
 * Credit: Yoast Developers
 * Last Tested: May 18 2019 using Yoast SEO 11.2.1 on WordPress 5.2
 */
 
add_filter('user_contactmethods', 'yoast_seo_admin_user_remove_social');
function yoast_seo_admin_user_remove_social ( $contactmethods ) {
 unset( $contactmethods['myspace'] );
 unset( $contactmethods['wikipedia'] );
 return $contactmethods;
}

Typically code snippets are added to your theme’s functions.php file. If you’re not familiar with using code snippets, these articles have wonderful advice:
http://www.wpbeginner.com/plugins/how-to-easily-add-custom-code-in-wordpress-without-breaking-your-site/
http://www.wpbeginner.com/beginners-guide/beginners-guide-to-pasting-snippets-from-the-web-into-wordpress/