Honestly, I think the 'mythic item' trope gets way too oversimplified in a lot of mainstream series. It's not just 'touch the thing, get the power.' In older series or more tactical manga, the acquisition is only step one. The real story is in the binding or synchronization process, which often requires a personal cost or a trial that mirrors the item's nature. A sword that demands blood sacrifice might psychologically break a pacifist wielder before they can even lift it, forcing a character evolution that is the power gain.
Look at 'Berserk' with the Berserker Armor. It's not a clean boost; it's a curse that grants strength by eroding the user's humanity and self-control during combat. The 'power' is inseparable from the degeneration. Or in 'Jujutsu Kaisen', cursed objects like Sukuna's finger are poisons that offer strength through possession, a constant internal battle for dominance. The power gain is a volatile, ongoing negotiation, not a deposit into a bank account.
Modern isekai has kind of flattened this into a video-game logic, which can be fun for wish-fulfillment but loses that deeper, often horrific, symbiosis. I miss when these items felt like making a deal with something ancient and indifferent.