How to filter out entities hidden by default in jinja template?

{{ area_entities("bedroom")|reject("is_hidden_entity")|list }}

is_hidden_entity only filters out entities that I manually hidden. But there are a lot of entities that hidden by default and not being displayed on default panel. How to filter it?

Describe what you mean “Hidden by default”. There’s likely no way to do this without applying filters to the list by emulating what is hidden in “Hidden by default”.

For example esphome has diagnostic entities. It is not displayed on panel by default. But get listed in example above

What do you mean by a “panel”?
Is it some autogenerated dashboard? If yes - then these entities are not hidden, they are just not shown automatically on an automatically generated dashboard, but you can manually add them on a “manually managed” dashboard.
Is it Settings->Entities? If yes - check if any filters defined to prevent these entities to be displayed.

You have to filter those manually, there is no template option at the moment. There is a PR for it though here if you want to add comments.