TV digital audio - Home theatre vs Stereo audio

Hi,

I have a question that is confusing me quite a bit. I just set-up a brand new 2 channel system which also has a Oppo BDP-95 Blue Ray player from my legacy system and a new OLED LG 4K TV. I trying to get the best sound from my TV. I usually view sports through the now-TV (cable TV provider in HK), Netflix (through my TV connect) and Blue-ray through my Oppo.

The TV has a HDMI ARC connection and an optical digital audio out. Currently I have connected the optical digital audio out to my Auralic Vega G2 DAC and then play the TV audio through my McIntosh/ B&W Diamond 2-channel set-up. I also have connected the digital Coax output from my Oppo to the Auralic DAC and hence I have bypassed the Oppo DAC as I consider the Auralic DAC superior.

However, I read up some material saying that an optical connect from the TV and the Coax output from the Oppo will not carry full Dolby Atmos and other higher end digital audio from the Blue-Ray and hence the audio from both my blue-ray discs through the Oppo and the Netflix that I play through the TV will both be downgraded to normal 2-channel audio.

My question is that if I anyways have only a 2-channel music system set-up through which my TV sound plays, does it matter whether I use the optical out from my TV or the more advanced HDMI ARC?

The second question is that the only way I can see to get the higher end digital audio is to buy a surround sound bar and connect it through the HDMI ARC connect on the TV and play the sound through the sound bar rather than the 2-channel set-up. The problem is that I do not have space to keep the sound bar and hence will need to go through substantive pain to get this done. Is it all worth it?

Thanks in advance.