Yeah, I've thought about that too. Original content for e.g Netflix probably never sees a physical release. As my earlier post probably alluded to though, we don't really watch a lot of TV in our household so narrowing my 'options' is not per se a thing that would impact me.
But it does suck for those who want to move to more physical-based media _and_ enjoy original content from the streaming providers.
Netflix does surprisingly release physical media now and then. EG: Stranger Things just got a complete 4k UHD physical release.
One very nice thing about physical media is the quality is often far better than you will ever get streaming, and this is true even on non-4k releases (though, especially on 4k). Audio is often the thing the streaming providers compress the heck out of.
IMO, Blu-Rays often go too far and waste bits on multiple multi-gigabyte tracks of lossless audio that would have been much better spent on increasing the video bitrate. Less of a problem with 4K on BD100 discs but still...
Have to take things into your own hands these days and grab the 2160p Dolby Vision streams and stuff them onto a BD-R, if you know what I mean.