Buying a Star Trek series on disc gets you the definitive version. The best quality picture, audio, as well as extras.
It's hard for me to understand why a "real Trekkie" wouldn't want it. Streaming is more convenient, yes, but you're dealing with slow internet speeds, annoying pixelation, and the fact it won't always be available.
I am sure there are many examples in this thread and countless other forums, folks will be talking about Blu-ray/4K/CDs etc and folks always have to come along, don't add anything to conversation but state that they stream everything like it is some unknown magic that only they are aware of. of course you stream everything, even people who buy discs stream most of their stuff. I don't buy anywhere near as many discs as say 15 odd years ago but my favourite films and TV shows still get bought. Lossless audio, less compression and extra features. Those new documentaries on TNG and Enterprise where some of the best extras I have seen. Plus I go to the extreme and rip everything (uncompressed) to my NAS and have my own sever of all my favourites.
I was referring to the information about the cameras they are supposedly using on the show.
Even if it was produced using traditional film you could still do a 4K transfer, the resolution of 35mm far exceeds that of HD and even 4K. In fact using a 2.8k camera has gimped a proper 4K transfer the best we can get is a 2K HDR transfer like most new modern movies.
In the case of several of the Trek movies, the mastering for blu-ray hasn't been quite up to "definitive version" level.
Kor
It will still be better then the streaming version, you still get extras and lossless audio. The version on streaming sites will still come from the same master, and this is down to Paramount being cheap and not doing new transfers for the Blu-ray release. The new remaster of TWOK shows how good they can look.