I may be a pendant in all this, but I think its very generic, and not all the helpful, to talk stand mount v floor stander at all. Especially for any "newbies" that may come across this thread.
There are many examples of stand mounts with large internal volume and large capable woofers and subsequent good and deep bass response just as there are many floor standers with small internal volume and small bass drivers and hence limited abilities bass response.
As just one example JBL have some massive stand mounts, past and present and compare that to and of the many slim tower floor standers that are so trendy today - Totem Arro a classic example.
The real issues are any, however, in room frequency response ( generally more bass with larger internal volume and woofer size) and dispersion (generally better with small frontal area and appropriate size mid and treble drivers ) are some common factors