Is this a new trend?

I think the speaker on a stand is a more appealing, sleeker look. Most important is it allows for better subwoofer performance rather than having the woofers connected in the same box.  

The term "bookshelf" speaker isn't really a fitting term for many of the stand speakers being used.

I think that this is no longer 1978. Folks entertainment time, and funds, are split between social media, video streaming, gaming, etc. And young folks are not buying houses at the rate that previous generations did (could be the prices), and so are in smaller, multi-purpose, rooms.

Audio as we know it is a dinosaur and a very niche dinosaur at that, IMHO, and YMMV.

yogiboy, Acoustic suspension was instrumental in the early design of small speakers but it is essentially dead these days. Thiel/Small research into the design of bass reflex speakers allowed the design of small ported speakers which are more efficient and bassier although usually with less bass definition. Today the concept is misunderstood and almost everyone including reviewers call any closed box acoustic suspension when it almost never is. Acoustic suspension is a special variant of closed box and all closed boxes are not acoustic suspension. In fact the drivers today have design characteristics for bass reflex and can't work properly in acoustic suspension boxes. Edgar Vilchur must be rolling in his grave after his concept once had 2/3 of the audio market before Thiel/Small.

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@viridian has a point. The number of houses I've been in even in my own Gen X that still have floor standing speakers is pretty minimal. Anybody who has anything up from a sound bar usually has a pair of bookshelf speakers. Maybe a sub if they're feeling really frisky. And Millennials and gen Z? Do you think they want to deal with floor standing speakers, especially those who stream most of their stuff?