The thing is, they're never gonna give you a starting weapon that doesn't have crappy, starting-level stats. Doesn't matter if that weapon used to be the Ultra Super Mega Infinity Blade of Great Justice + 1. They've got a difficulty curve to maintain.
Exactly that. It was the same with The Witcher 1 to The Witcher 2. The Moon Blade was the best silver sword, the Mahakan the best steel and Raven's armor the best armor. At the second game they were but a glimpse of their previous versions. You can have the Vran Armor, the Caerm ( or Forgotten Vran) Steel the best silver sword, at The Witcher 3 they are gonna be low end gear. If they were top notch, why we would hunt for epic equipment and with better stats?