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Right now the median fee is about $2. After lots of halvings the reward won't be enough to satisfy the miners.
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In my opinion, in the future, where all the bitcoin's have already been mined, the transaction fees will get higher because these miners does not have taking any rewards. The only money that they can take is from the transaction fees from every single blocks they were able to create. I don't know what will happen next because of this. We'll know if we get there.
As they said, there will be an equilibrium that will happen. And since we are still not talking about when all of the bitcoins are mined, as the difficulty increases, that would also mean that the transaction fees will increase because of the value of bitcoin also increasing. That is the effect of halving making it fair for all of us.