Well the thing about rng is the statistic isn't static because as we have already seen new jobs are coming down the pipe. So you statistical chance of getting what you want is declining so a token system works the best around this for specific items. And, don't consider rng a time sync, it isn't even though it acts as one to some there are many better time syncs that they could easily throw in as road blocks. Rng is based on the original table top idea that rarity is given to an item by limiting its appearance. The best way to do that where its "fair" so all players can access it is statistical drop rates that are base on a random number generator. Which is much more socially acceptable then only one Excalibur on the server so if you don't get it you have to search for a next best thing. Which to be honest is even more fair in the real world scheme of things but can you imagine the complaints that this person is better and you can not reach that plateau because it literally no longer exists. Similar to how eve where new players will always be a disadvantage because leveling is time invested.