Do You Need HDMI eARC For Dolby Atmos? –

One of the main benefits of using HDMI eARC for Dolby Atmos lies in its name. HDMI eARC allows for a more enhanced audio quality to be transmitted. Dolby Atmos technology uses object-based sound, which means that individual sounds are treated as separate objects, rather than being part of a fixed channel.
HDMI eARC and Dolby Atmos are two technologies that have become popular in recent years. They're designed to create home theater experiences that rival cinema experiences.

HDMI Audio Extractor for Dolby Atmos, DTS-HD - FeinTech

OREI eARC 4K 60Hz Dolby Atmos Audio Extractor Switch with 3 Inputs - Connect ARC/eARC Soundbar. HDMI 2.0 and HDCP 2.2 Compliant - CEC Pass Through - HDR, Dolby Vision Supported (HDA-934) : Electronics

How to use the Sonos Arc on a TV without eARC (and get Dolby Atmos)

What is eARC and how does it compare to HDMI ARC? - SoundGuys

What is HDMI-eARC/HDMI 2.1 and How Does it Differ from HDMI-ARC? – Klipsch