I meant to have a look at this again more quickly, but I have had a chance to investigate further now, and I am still having this problem.
Site info:
Wordpress 6.4.2
Pro 6.4.8
No child theme
All plugins temporarily disabled
I’ll add access details in a secure note for you to look at the setup as well and maybe shed more light on the problem.
On the Homepage, I have added two buttons in the first content banner (the “Modular, scalable, easier to deploy” section)
The first button is a custom Component button that I have built, and then enabled Customisation for, to add the Custom Attribute. This one has a simple Custom Attrible title
set to {{dc:post:title}}
.

This is parsed correctly in the preview window, but not in the front-end.
The second button is just a default button element, with the Custom Attribute added exactly as with the component. This one is parsed correctly both in the preview window and in the front-end.
Seems that something to do with the Component is causing the Dynamic Content to not render correctly.