Thats not a relatable comparison, your still missing the boat on this. Audio quality is more then just data on a file.
Even if you have 1,000,000 GB's down, and all the same equipment as I do, same receiver, digital cable, everything, the direct source to source content from the disc would be clearer, crisper and superior. It's not about size, or bandwidth. It's about what it has to go through to get there.
Sorry but this is nonsense, my friend. You are arguing that the issue is compression/not being "direct digital to digital" but this isn't true. In fact, the "uncompressed" data on your discs is actually compressed as well.
Also, this statement about "more than just data on a file" is false. When it comes to digital data, it is LITERALLY just data and reproduction of that data is 100% accurate. This is true whether you read it directly off a disc or stream it thousands of miles over the Internet.
So what gives with the poor streaming quality, then? Well, streaming services don't bother to stream the top-quality audio data you can find on the disc, that's all.
Yep. It's as simple as that. They could, they just don't.
It has nothing to do with the disc being in your house and directly connected to your TV, that's nonsense. If the streaming companies involved wished it, they could easily stream full quality DTS-HD Master Audio to your house along with the video. You'd need about 30Mbps to do so, which is within the realms of some home Internet connections these days.
Why don't they do it, then? Because it's not worth their time and money. It costs more to store that extra-high-quality data in their datacenters, and it costs more bandwidth to stream that extra data to your house. That costs money. And lots of people using their services still don't have fast enough Internet anyway and couldn't stream the data in real-time if they wanted to.
Streaming services take the view that their customers can't/won't notice the difference if they drop the quality a little, or at least won't be bothered by it sufficiently to stop using the service. Sometimes this gamble doesn't pay off (Crunchyroll got in trouble not long ago for a sudden drop in quality on their service which plenty of people did notice, for instance).
Once again: it has NOTHING to do with the fact it's compressed, they make a deliberate choice to use more highly compressed audio and save on bandwidth and storage, it's not a limitation of compression itself. The audio on your discs are compressed as well, just using more bandwidth-intensive, lossless algorithms. It would be easily possible to stream a full-quality blu-ray experience if you had enough bandwidth and you WOULD NOT notice the difference, guaranteed. But you would need a 150Mbps home broadband connection to do it.