If I am not mistaken only eARC can do Atmos and DTS:X , so if your TV has eARC instead of ARC then you will be able to get Atmos.

It’s worth noting ARC doesn’t allow you to bitstream the full-fat high-quality codecs such as Dolby TrueHD, Dolby Atmos, DTS-HD Master Audio or DTS:X soundtracks that you find on Blu-rays and 4K Blu-rays. It simply strips out the core 5.1 data stream. If you want this level of functionality, you’ll need HDMI eARC.

ARC can, however, allow you to receive Dolby Atmos audio from streaming services that use the format, including Netflix and Amazon Prime Video. These services embed Dolby Atmos in a Dolby Digital Plus stream, which ARC can handle.
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Enhanced Audio Return Channel (also known as eARC) is the next generation of ARC. It’s a feature implemented in the most recent HDMI 2.1 specification.

The main benefit of eARC is a big boost in bandwidth and speed. This allows you to send higher-quality audio from your TV to a soundbar or AV receiver.

There’s scope for eARC to deliver up to 32 channels of audio, including eight-channel, 24bit/192kHz uncompressed data streams at speeds of up to 38Mbps.

I think this Sony model of mine can't support it. It only has arc. Not earc.

Netflix UHD 4K HDR10 / dolby vision content so limited. I don't use other streaming apps so not sure about the content for others.