I remember that widebody aircraft were marketed as giving passengers more space (anyone remember BEA's TriStar advert with the slogan "European Space Travel"?)
BOAC initially planned to have 9-across in economy on its 747s but this soon became ten. As load factors rose economy widebody travel became more uncomfortable. The days of having acres of free seats, say, between Perth-Melbourne-Auckland on BA disappeared as greater distances could be flown nonstop. I seem to remember DC10s had 5-across in the central section. Yuk! (I may be wrong about that.)
In more recent years I recall deliberately seeking out single-aisle aircraft for transatlantic travel, e.g., Canada3000 757s. This was once I'd overcome misgivings about ETOPS! Last but not least, the numbers milling around at baggage reclaim were much lower.