In a word, yes. The vintage trailers' (ie., from the 60's) claim to fame was their light weight. Airstream went to great pains to keep them as light as possible. As time has moved on, and tow vehicles have become more capable, and owners have developed a taste for wider trailers and more solid construction (ie., solid wood cabinetry) they have gained weight. Some of the smallest new trailers available today weigh approximately as much as some of the largest trailers from the 60's.
good luck with your search!