For sure there is acoustic differences between bookshelf and Stand-mounted and Tower speakers ...
As there is difference between different speakers types too and not only about their sizes...
Acoustics taught us that there is a trade-off for each size and each types in relation to each room geometry and size and in relation to specific needs ...
Then debating what is the best does not means much ...
Acoustics taught us that we can use any types or speakers sizes optimally or not ...
The soundscape perception can be created by acoustic knowledge from any speakers...There is a trade off for sure between the acoustics factors in relation between types and size... But the good news is that we can create a relatively good High Fi soundfield with any speakers well embedded ...
My personal ultimate criteria is not size or types, more S.Q. levels/ price ratio...Because i dont have a big room now nor a unlimited budget ,...
But i dont mind, i use acoustics knowledge to shorten the distance between the best S.Q. possible and the optimal one for a price level ...
And it is not only enough to be acoustically happy, it is enough to smile at the astronomical prices paid by some compared to my own speakers value ... But for sure without modifications my active speakers are not good at all for me...Acoustics knowledge is way more than buying panels ...
We are all different in goal and tastes and needs... This is why i am very proud of my 150 bucks active speakers which modified gave me 50 hertz from their 4 inches woofer and a soundscape that made me smile with pride not envious at all but in the opposite almost taking pity of those who had invest way more for sometimes way less ...😁