These sturdy leather bags look really good, but aren't they heavy? I had a regular Samsonite backpack (made out of plastic, not leather) that lasted for over 10

These sturdy leather bags look really good, but aren't they heavy? I had a regular Samsonite backpack (made out of plastic, not leather) that lasted for over 10 years of almost-daily use - actually it's still in Ok shape, but I don't use it anymore.