Joomla 4 - Module assignment to page or pages now required ?

We are converting our site to Joomla version 4.
I have noticed a difference in Joomla 4 when adding a module to a PageBuilder CK Page.
In Joomla 3 when you added a module to a page you could specify option Module Assignment to No Pages.
However under Joomla 4 if you specify the same option, the module does not appear on the output of the PageBuilder CK Page.
You now have to set the assignment to either the menu item or all pages.
Why is this?

Hi
the module assignment has not changed between Joomla 3 and 4
if you set "no pages", this makes the module to not render at all
you must set it to "all pages" instead and publish it in "none" position
CEd

Very Strange.
Under my Joomla 3 modules appear with 'No Pages' Set.
See attached screen shot of Page Builder, Module and Output. You can see module is set to no pages, but does appear on the Page Output????
It is not a problem for me with Joomla 4 setting all pages, so please don't waster time investigating.
Thanks for the clarification.