I am not against larger subwoofers but I am of the opinion that smaller ones that are capable of doing the job in general are preferable. Larger high quality subs may cost a lot more and offer no distinct advantage or be needed in many cases. Also larger subs are heavy and harder to handle and perhaps even place properly in some rooms where space is limited.
For my smaller 12X12 room, for use with a pair of KEF ls50s, I chose this model that is unusually extended for its size due to use of two passive 8" drivers to supplement the main 8" active driver. This is a really good combo!!!
https://www.klipsch.com/products/sw-308-subwoofer
The KEFs are small with limited bass extension so a smaller sub fits in well there.
Granted that it will likely take a larger more extensive sub to merely fill in the lowest octave well if used with larger more full range mains.
For my smaller 12X12 room, for use with a pair of KEF ls50s, I chose this model that is unusually extended for its size due to use of two passive 8" drivers to supplement the main 8" active driver. This is a really good combo!!!
https://www.klipsch.com/products/sw-308-subwoofer
The KEFs are small with limited bass extension so a smaller sub fits in well there.
Granted that it will likely take a larger more extensive sub to merely fill in the lowest octave well if used with larger more full range mains.