A forked and modified version of Bill Erickson's "Disable ACF Frontend" MU plugin that adds some extra checks for front-end requests.

hny-disable-acf-on-frontend.php

<?php
/**
 * Plugin Name: Disable ACF on Front-End
 * Description: Provides a performance boost if ACF front-end functions aren't being used.
 * Version:     1.0
 * Author:      Honeycomb Creative
 * Author URI:  https://www.billerickson.net/code/disable-acf-frontend/
 * License:     MIT
 * License URI: http://www.opensource.org/licenses/mit-license.php
 */

/**
 * This is a forked and modified version of Bill Erickson's
 * "Disable ACF Frontend" (http://www.billerickson.net/code/disable-acf-frontend/).
 *
 * Adds some extra checks for front-end requests.
 * For instance, plugins installed/deleted via WP CLI would (annoyingly) trigger ACF deactivation.
 *
 * @param array $plugins List of plugins.
 *
 * @return array
 */
function hny_disable_acf_on_frontend( $plugins ) {
	if ( ! is_admin() && ! defined( 'WP_CLI' ) ) {
		foreach ( $plugins as $i => $plugin ) {
			if ( 'advanced-custom-fields-pro/acf.php' === $plugin ) {
				unset( $plugins[ $i ] );
			}
		}
	}

	return $plugins;
}

add_filter( 'option_active_plugins', 'hny_disable_acf_on_frontend' );