Streaming has gotten much better, and is certainly convenient, but it still can’t touch the video and audio quality of physical discs. If you have a good to excellent home theater system, the audio in particular is vastly superior on disc. As with the video, the higher quality is because discs can provide much higher bitrates.
I’m afraid, though, that middling quality will be seen as “good enough” by the masses, and home theater will suffer the same fate as high quality two-channel audio for music when MP3 crowded out far superior formats.
Just to clarify before someone jumps on my comment, I was referring to 4K Blu Ray discs, not the older 1080p discs.