I spoke to my local librarian who cited this as the reason they haven't bothered with 4K blueray despite it being 10+ year old technology at this point.
Think of it from the point of view from senior citizens. They likely already have the equipment for DVD and are used to it. That alone is "simpler to operate". Yes Bluray could often have simpler menus but that existing inertia is something that is important as well because I dont think most senior citizens are actively seeking out newer tech if they dont need to.
In case you're asking "why", it's because your "4K" stream is compressed to hell and back. Your home internet connection doesn't even have the bandwidth to stream the quality of a BR.
This has not been true for most people for a while now. Even the high end of 4K blue rays tops out around 100 Mbps, which is achievable on pretty much any broadband connection.
It's only achievable in a real sense if there are video providers out there offering the content at that bitrate. The absolute best you can hope for in optimal conditions is from Apple TV+ at between 30-40 Mbps which is equivalent to what you get with a non-4k blu-ray.
The media includes bonus features that generally aren't available in streaming or torrents.
The media will not suddenly stop existing if some server breaks down, some company goes under or some contract expires.
The movie will not suddenly get "patched" with an AI-upscale or censored scene one day while watching it.
You can lend the media to someone else to watch without having to ask for permission to anyone else.
AVGN complained about it here: https://youtu.be/tetXKdi9U3c?t=400
Is that really a thing?
Blu-Rays also have special features, which most streaming platforms don't offer (I think largely except for iTunes).
I want to support artists who make content I like, but I also want control over my media library. Physical media is the best way to do this.