Update, remove or redirect the posts menu item.
<?php
return [
'wp-admin.$role|$username' => [
'posts',
'posts' => (string) $route,
'posts.title' => (string) $title,
'posts.icon' => (string) $dashicon,
],
];
Remove from menu;
<?php
return [
'wp-admin.$role|$username' => [
'posts',
],
];
Remove from menu and enforce a page redirect;
<?php
return [
'wp-admin.$role|$username' => [
'posts' => 'pages',
],
];