No Optical socket on the new Apple TV

You are expected to use the audio passthrough option of your TV.

Apple TV →[HDMI]→ TV →[optical]→ receiver without HDMI

If that is not feasible, then you may consider an HDMI Audio Extractor.

Apple TV →[HDMI]→ HDMI Audio Extractor →[HDMI]→ TV

↘︎[optical]→ receiver without HDMI

For receivers with HDMI, there is good reason to avoid optical, as it limits the audio options.

Apple TV →[HDMI]→ AV receiver with video passthrough →[HDMI]→ TV

or

Apple TV →[HDMI]→ TV with audio passthrough over HDMI ARC →[HDMI ARC]→ receiver

Thank you !