This is a great topic. I have flip-flopped back and forth on this a couple of times. Again, it comes down to your room.

There is a simple argument that the optimal placement in a room for midrange and treble will differ from the optimal placement for bass. If speakers and subwoofer are in separate locations that are optimized based on your room, soundstage will be better than a floorstander which will have to compromise one or the other.

There are tiny timing issues, etc... that make this slightly sub-optimal.

That being said, in a perfect world, you would treat your room so that optimal bass, midrange and treble performance would occur in the same location. Then a floorstander would give you the best possible soundstage.

I have been in showrooms that are treated where floorstanders sound incredible and deliver amazing, immersive soundstages and others where they sound flat.

My feeling is it is easier to get a standmount and subwoofer(s) to deliver an amazing soundstage in a room vs. a floorstander simply because the room will need less treatment.

Again, must disclose in every post. I am the founder of Verdant Audio Inc, maker of Verdant Speakers, importer for Art Audio and re-seller of a variety of brands.