should I hookup my Apple TV device to my AVR or TV ?

Either way will function, but one of these might be preferable based on specifications and limitations of the components.

• Modern AV receivers are often known for having more HDMI ports than TVs, making them the better hub for connecting devices to.
• TVs without eARC will be limited for audio passthrough.
• Older AV receivers may not have the modern HDMI 2.0/2.1 ports for 4K HDR video passthrough.
• Dolby Atmos capable AV receivers are ideally the first connected device, as described.

Set up Dolby Atmos or surround sound on Apple TV with a sound bar or AV receiver - Apple Support

Play audio in Dolby Atmos or surround sound on your Apple TV - Apple Support

My receiver has ARC, not eARC, but my TV has eARC but it is turned off. Currently I have my Apple TV 4K connected to my TV, not the receiver. Is this the best way way to get the most from my setup? Am I getting the best overall performance pushing everything HDMI to my receiver? I realize both work, but what is better? It's very convenient to only have to use my Apple remote for everything and not have to switch inputs on my receiver.