Many consoles come with one built in. We just use the PS5.
I'm not particularly into buying tv shows, but there are definitely quite a few movies out there that look a lot better on a 4k blu-ray than 4k streaming.
I got a PS5 with a 4k blu ray player but have yet to put a disk in it since many films are simply not available. Tried to find Lawrence of Arabia but it seems completely unavailable. Maybe the format is great but lacking lots of content.
So it looks like they finally released it in June this year, but only as a $120 limited edition. Before that it was only available as part of a $290 Columbia Classics box set. Think I'll pass.
It was actually released at a normal price (I think I paid $20 for it), but yeah, didn't realize it was a limited release that's now going for big money.
(The limited release thing is annoying, but... it's a niche market, and one of the ways they get people to buy things at full price instead of waiting for 50% sales, so I get it.)
It is pretty rare for me to buy movies on physical media, but I do sometimes buy some. I only really buy movies that I would want to share or watch again some far time in the future and don't want to risk getting de-listed from whatever streaming sites I have access to.
The vast majority of video content I consume I probably wouldn't watch more than once. But in the rare cases where I'll probably watch again and want to share it with the future, I'll buy it on physical media.
I do this for other physical media as well. There's been some music I have on vinyl or CD which I can't find on Spotify or for digital download. Most music I wouldn't care if it disappeared tomorrow, but some I'll want to have in the future for sure.