nope, incorrect. that occurs when the manufacturer goes from a smaller sub to a bigger sub without increase motor strength to keep the TS parameters similar for similar performance. Its literally what you get with garbage tier woofers. With any properly made subwoofer brand, going from a 10-12-15-18-32 mainly affects output, does not affect punchiness or snappiness at all. That literally all enclosure and enclosure size/design is A LOT different when going up in sub size and takes a lot of work. Whatever you read is from a bunch of noobs that most likely used pre-fab ported boxes and dont know why their subs sound like complete sh*t. Pretty much the same people that say sealed boxes hit more notes than ported... complete noobs. As long as the sub is balanced with motor strength (BL) to moving mass ratio and their QES, QTS and QMS factors, it'll give the same punchiness at any size. You got people winning sound quality comps with 18s and 15s, its literally all in the install and tune.
for placement with best phasing in a trunk.