Field group #states interferes with children #states

Actually, I think this is more likely a Field Group issue as it still happens if I remove the Conditional Fields dependencies and use various form hooks to apply #states directly.

Some more detail:
- I have field group tabs and inside one of those I have a checkboxes element and a fieldset containing text fields.
- I have used hook_form_alter to add #states to make one of the text fields required depending on a checkbox value.
- I have used hook_field_group_form_process_alter (and a tried bunch of other similar hooks) to add #states to make the fieldset visible depending on the same checkbox value as per https://www.drupal.org/project/field_group/issues/1053174#comment-14138494 💬 hook_form_alter form state problems Closed: works as designed

What happens is that when there is a #states value on the fieldset, the required state is applied to all the text fields inside it.

I have used Conditional Fields module to make a field group visible (or not) and can confirm that once the FGis made visible; all the fields within it are made required. The red star even shows on the label for the FG itself.