In this case

[luojiandan]

May I ask a hypothetical question at the extreme end? If one day XDAG is mined out and there is no transaction fee or the fee is very low, what motivation do miners have to maintain the main network?

[LucasMLK]

I think Bitcoin has the same problem. In the future, we plan to add variable fees to increase miners' income through more frequent transfers, so not only the main block will receive rewards, but transaction fees will also account for a large part of the rewards.