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Personal reasoning: Destroying the item makes it too risky = too RNG based = leading to p2w. Since we don't want the game to go down that path, and since certain mmorpg's also started avoiding that, it's time we get with the program, too. Plus, it won't make things "easy", it just won't make them ridiculous.
The concluding idea we got to from the discussion thread was fine, I guess (break card = upgrade level back to 0, but still keeping the item). Though personally, I wouldn't make it instantly zero, and I would make upgrade stones harder to get instead. Such as them dropping only or mostly in dungeons, which makes people keep farming them after already getting the gear they want + farming more gear to sell to others in the process.
As for rates, you could make them a bit harder to balance it out, I suppose.
I support this 100%.
For some dumb reasons people fail to realize that removing the destroy item option doesnt make upgrades easier, it only removes frustation and RNG.