Comment by supermatt

In the example they are just using an empty <RadioGroup.Indicator/> for the pip as it is easy to target with a classname, but you can put any content in there instead for e.g. card-style radios (as used for complex selections, like a subscription tier).

By using radix, the underlying behaviour is compliant and identical for each of those implementations - you just change the content. Radix isn't looking at it like an html radio element, it is looking at it as a completely unstyled unique item selector.

The pseudo-element styling approach limits you to 3 layers - the container, and the 2 pseudo elements, none of which you can provide with meaningful content besides plain text. The best you can do is provide a basic styles and set background image. For anything else you need to use labels to either wrap the radio (in which case you can access state via sibling selectors) and/or ref them with "for" (in which case you cant access the state).