Depending on you exact equipment, it can be functionally and quality-wise the same. Whatever works best for you.
Apple TV →[HDMI]→ TV →[HDMI-ARC]→ Receiver
Then the TV has to passthrough the audio.
You would select the HDMI port for Apple TV as input using the TV remote.
Possibly preferable when your TV has more HDMI inputs than the receiver.
Apple TV →[HDMI]→ AV Receiver →[HDMI-ARC]→ TV
Then the receiver has to passthrough the video.
Selecting the Apple TV instead of other HDMI devices would be done on the receiver.
Possibly preferable when your receiver has more HDMI inputs than the TV.
Preferable for Dolby Atmos setups, to avoid ARC use, as regular ARC doesn’t have have the bandwidth for the Dolby MAT signal that Apple TV outputs. (TVs with eARC are meant to solve this, to work in setup #1 too.)
If either the TV or receiver doesn’t have HDMI 2.0/HDCP 2.2 ports, then that would have consequences that may make one option vastly superior to the other.
Use all HDMI cables certified for 18 Gbps to enable all HDMI 2.0 features. Lesser cables might restrict features.