WordPress 5.4 introduced the Site Health Status dashboard widget and with this came client insecurities!
If you’re looking to hide this dashboard widget for all users, just add this to your theme functions.php
add_action('wp_dashboard_setup', 'remove_site_health_dashboard_widget');
function remove_site_health_dashboard_widget()
{
remove_meta_box('dashboard_site_health', 'dashboard', 'normal');
}