Since 2010 I have been purchasing blurays only. I will occasionally purchase a DVD set of an old tv series from my childhood. I enjoy collecting blurays of older films that I know I will watch a couple times a year. For when checking out new films I'll just stream them. It has become so easy to stream just about any newer film or tv series. The majority of films released in the past few years have been quite bad, that I don't bother to buy them because I won't be watching them after the first viewing.
I absolutely still buy movies on both DVD and blu-ray, and I still have a large collection of VHS tapes. I also stream, which is an excellent way of checking out new movies, but I'll always buy a physical copy any movie that I particularly like. It's always useful to have some back-up for when the internet goes down...
Definitely still buying DVDs and blu-rays. I just don't like the idea of Netflix. When rights expire, so do the films. I'd rather have the movie 100% available when I want to pop it in and watch. That's why I would always purchase the films I like.
The past is history, the future is a mystery, today is a gift--that is why they call it the present.
I still buy DVDs, which I prefer to blu-rays. But I don't double or triple dip. The Universal Monsters is a good example--seems every year or so, some new Legacy edition is issued, or they've cleaned up the soundtrack or tweaked it this way or that. And they're selling still another version of it. I already have three versions of The Wolfman in my collection--do I need still another? No.
I had a pretty decent DVD collection. I've stopped just because of the ever changing formats. I'm not going to constantly keep re-buying films. Especially now with so many of the movies readily available on streaming services.
I'll still collect and buy my "must haves" (Star Wars, Bond, LOTR, etc.) but the rest I'll rent or catch on Netflix.