From my experience, MDF and particleboard furniture usually weighs more due to the higher density of the wood and glue vs. traditional wood furniture.

Well, let's do this right.

Make plywood with the middle being balsa, and the surface being lignum vitae.

That is something that really surprised me, how light this "real wood" desk was (made from Poplar wood), compared to another similar desk that the wife bought a few months earlier (before the covid at-home back-to-school rush caused a desk shortage).

My recollections of helping people move disagree with you.

I've only had one piece of real wood furniture that was ever close. That was made out of rock maple, which turns out to be a very accurate name.