It's stupidity and completely ruins the rarity of an item. When you saw somebody with that hat, you knew they were an old player. Now people with 50 hours will have it. Whelp, how about we resell every hat while we're at it? No point in rarity, right?

Bringing back old hats doesn't give anybody a nostalgic feel, it irritates people that the rarity of their item got completely screwed over. That's like if event hats started getting sold.