For one, very few people buy physical media anymore - but streaming isn't licensed like physical media is, so while you can buy the disk form of virtually any movie without any hassle, you may have to sign up for a specific subscription service or platform to stream. For example, I would need to sign up for Comcast to stream "Cannonball Run" - but I can buy it on DVD from Amazon.
It also means that anything that isn't available to stream, anywhere, doesn't get watched the way it might if we were still in the Blockbuster era.
And of course, missing bonus features and special cuts of films is yet another major change.
On the whole, I've been able to consume far more content that I love thanks to streaming than I think I've lost because of it. But it's worth noting the changes. Will definitely check out Criterion's service.
I like the concept of streaming services that cater really well to one specific interest. I also like that I can do what I describe, and pick and choose which subs to maintain based on my interests at the time.
I do miss the good old days when Netflix had everything, but nothing lasts forever I guess. That is, besides the thrilling salt air of the wide open seas ;)