I been a collector of physical media for over 30 years now. I do find the picture and sound much better on disc compared to streaming but I'm also selective to what I purchase currently and just fine with most streaming quality.

Top Gun Maverick is an example of a poor streaming film where the 4K UHD disc is simply incredible. I will note I own a home theatre with Dolby Atmos.

Currently Disney is investing more to streaming, so their physical disc are bad to average. Although they just released WALL-E on 4K criterion but really it's hardly an upgrade from the 1080p blu-ray. You can say that with most of their 4K disc.

Some classics on 4k UHD are like seeing them for the first time, The Shining, My Fair Lady, Lawrence of Arabia just to name a few.

It is a $$$ commitment that's why I would suggest if you really want to invest into 4K UHD to do the research and check reviews from blu-ray.com get the right equipment, screen, sound