The reality is that it’s all a value proposition between money as a stable income with the off chance that it gets disrupted by the world price of oil and the price of money as a lump sum. Some people do not want to deal with the hassle of maintaining the ownership through taxes or someone comes to them willing to pay significantly more than they have ever seen.
It is totally up to you. Do you need the income? Do you not need the income? If not, what is the harm in holding onto the minerals? They are a finite resource. Who knows what will come from holding on to them.