I think that's probably true. My personal experience is that floorstanders with this kind of bass response tend to sound a bit on the lean side unless placed close to a wall or used with subs. From one perspective, this makes sense I suppose, as these are essentially speakers with little or no baffle step compensation.
Of course my subjective experience may not place me among the majority here... An alternative way to look at this would be to say that floorstanders are always in 2pi space and that their response should not be considered in isolation from the floor's boundary reinforcement. That would lead to a design methodology that called for a shelved-down bass response in floorstanders (
@BYRTT demonstrated this well with graphs in an earlier post). This doesn't seem correct to me, nor does it match my experience, but I think arguments could be made for it.
I haven't been keeping track of all the measurements. What other floorstanders have been measured? The only ones that come to mind are this, the F208, and that one JBL (which measured more or less as expected in the bass IIRC).
Knowing the woofers used in the F208, the bass response doesn't surprise me too much. The 8 Ohm versions in particular need large enclosures to play low, and moreover the low relatively steep crossovers tend to knock down the low-bass response an additional few dB around the impedance saddle centred on the port tuning.
The woofers used in this 328Be are more of an unknown, but assuming they share essential common attributes with their F208 cousins (which is a big assumption of course), three of them in a cabinet this size does seem to me like a lot of woofer in a relatively small enclosure volume, which (along with the low, steep XO filter) would similarly tend to lead to limited bass extension (despite the low port tuning).