Disagree. 2016 15" MBP was 4.0 pounds. 2019 16" MBP was 4.3 pounds. New 16" MBP is 4.5 pounds. Apple simply decided in 2016 to shrink the size and weight by removing ports and other things, and then to increase the size and weight by bringing them back.

Personally I'm surprised they didn't decide to keep the same weight by shrinking the battery. Not that many people absolutely need a 21 hour battery life, though it is nice.