Hi Carlos,
Thank you for writing in, No, it is not hidden on purpose on contrary we strongly recommend using the Pro Content Editor when creating a page.
Yes, it is true that the WP Gutenberg editor is the default editor when you first create a page (because that is the native Wordpress editor), but after you open/edit the page in Pro Content Editor that page will be associated with Pro Content Editor moving forward.
It’s actually easy to open/edit a page in Pro Content Editor than what you describe above, please see this clip.
If that is not what you’re seeing on your end, please do testing for a plugin conflict. You can do this by deactivating all third party plugins, and seeing if the problem remains. If it’s fixed, you’ll know a plugin caused the problem, and you can narrow down which one by reactivating them one at a time.
Cheers!