Does SXG now works with custom hostname setup?

It’s been quite some time since the release of Signed Exchange (SXGs), but I’m not sure if it is currently working for SSL for SaaS based custom hostname users? Does anyone know? I tried it enabling SXG on a custom hostname using Configuration Rule as it is disabled by default at the zone level — but I’m not seeing any CAA record being added to that domain whcih I checked via https://caatest.co.uk/ which made me wonder if it is even working for these custom hostnames or not.

Does anyone have any idea?