HI @henrydouglas,
The above would be the default behaviour, ie, all users once logged into the website will have the admin bar visible in the frontend.
Is it specific to any user role?
If the issue is specific to the admin bar not showing up, then please do check the following & see if that helps:
https://rankmath.com/blog/fix-missing-admin-bar/
Looking forward to your response.
Regards,
Nithin
I think you can control that with this hook here: https://developer.wordpress.org/reference/hooks/show_admin_bar/
There used to be a plugin that provided this function. Unfortunately, it was closed at the request of the author. But you should be able to develop something like this individually with the above hook.