AMP or Receiver for DT770(25ohm) headphones?

So, I'm definitely buying an LG SNY6 Sound bar system, it's more for aesthetic reasons and saving space rather than opting for a couple of book shelf speakers. Sound is only important to me when it comes to headphones since i'm in an apartment. The Soundbar will be boarder line useless and at low volume anyways.

But, it's confusing because if i buy something like a Sony DH790 Receiver, i'll be using it's eArc HDMI port and sending that directly to my OLED, and then the Nintendo Switch & PS5's HDMI will be directly sent to my TV to avoid any Receiver video pass through. The Receiver is strictly for headphones, but spending $599 CAD just for that seems like a waste imo.

The main issue here is the sound bar above uses ARC HDMI which i would be using instead with my receiver. I guess i would have to use optical instead with the sound bar directly to my TV? Or if i went for an AMP instead would i be able to workaround the entire ARC HDMI, and just use ARC with the sound bar?