Moved to: https://wordpress.org/plugins/classic-editor-addon/

classic-editor-addon.php

<?php
/**
 * Plugin Name: Classic Editor Addon
 * Plugin Author: Pieter Bos (https://so-wp.com) and Greg Schoppe (https://gschoppe.com)
 * Description: The Classic Editor plugin doesn't remove Gutenberg by default. with this function we set the option that controls this from no-replace to replace and we remove the Settings link from the main Plugins page
 */


function classic_editor_addon_hardcode_replace( $value ) {
	return 'replace';
}

function classic_editor_addon_remove_settings_link( $links, $file ) {
	if ( $file === 'classic-editor/classic-editor.php' && current_user_can( 'manage_options' ) ) {
		array_shift( $links );
	}
	return $links;
}


function classic_editor_addon_init() {
	/**
	 * Remove the Try Gutenberg Panel, slated for WordPress 4.9.6 
	 */
	remove_action( 'try_gutenberg_panel', 'wp_try_gutenberg_panel' );
	if ( function_exists( 'classic_editor_init_actions' ) ) {
		/**
		 * Change the default option of "no-replace" to "replace",
		 * which means the checkbox will be unticked and the bloody plugin
		 * does what it says from the get-go (L336). 
		 */
		add_filter( 'pre_option_classic-editor-replace', 'classic_editor_addon_hardcode_replace' );

		/**
		 * Remove Settings link to the settings from the Plugins screen (L277).
		 */
		add_filter( 'plugin_action_links', 'classic_editor_addon_remove_settings_link', 10, 2 );		
	}
}

add_action( 'plugins_loaded', 'classic_editor_addon_init', 1, 0 );

Hi @gschoppe Greg,

I came to realise that the filter of the plugin_action_links with the classic_editor_addon_remove_settings_link function does not work.

To make it work, the filter needs to be replaced with an action:
add_action( 'plugins_loaded', 'classic_editor_addon_remove_settings_link' );

And the function itself can be simplified by:

function classic_editor_addon_remove_settings_link() {
	remove_filter( 'plugin_action_links', 'classic_editor_add_settings_link' );
}

You can see, the changes also in my original gist (updated of course with your changes).

What do you think about releasing this together as a plugin in the WP Plugin Repo?