The same principle has remained true for the entirety of the church's existence.
The prophet brings forth the word of the Lord to his people as they are able to receive it. And of course the prophet can receive revelation for himself independently.
Let the prophet receive for himself as far as he is prepared, he will only receive for the people according to their willingness to listen. Of what purpose is it to move on to the next principles when we are already finding condemnation for not obeying the ones we have. Isn't it more sensible to come out from disobedience to the first which was easier before being given the second which will require more from us?
Now there is more to this that needs to be said. Must the people have faith equal to the prophet's for the prophet to receive the word of the Lord for them? No, or they could have gotten the revelation for themselves.
They must depend upon the chosen vessels of the Lord for the word of the Lord. And if they will pay heed to it then they will be given more. But there is an enormous difference between what the Lord will reveal to them in their disobedience, and what the Lord is willing to reveal privately to his prophet in his obedience.
They are at different levels, and the one reaches down to lift up others to his level. And even as he does so, those above him beyond the veil are reaching down to lift him to a higher level, for he also has a long way to go, though not so far as those whom he leads.
As Joseph Smith said: When you climb up a ladder, you must begin at the bottom, and ascend step by step, until you arrive at the top; and so it is with the principles of the Gospel--you must begin with the first, and go on until you learn all the principles of exaltation. But it will be a great while after you have passed through the veil before you will have learned them. It is not all to be comprehended in this world; it will be a great work to learn our salvation and exaltation even beyond the grave. I suppose I am not allowed to go into an investigation of anything that is not contained in the Bible. If I do, I think there are so many over-wise men here, that they would cry "treason" and put me to death. So I will go to the old Bible and turn commentator today.
And there is still one more thing that needs to be said about this. The principle is not just that one reaches down and lifts those above one up to one's own level. The principle is that doing so is one of the primary means by which one climbs to a higher level. You need someone above you to give you the needed instruction, but you progress primarily by turning around and lifting those beneath you.
While not commonly noted, this is intended in D&C 76. The reason the terrestrial minister to the telestial is that in doing so they are glorified. The reason the celestial minister to the terrestrial is that in doing so they are glorified. That may be the role of those who are ministering servants, but who cannot have an increase. But the celestial do not minister in person to the telestial any more than God appears in glory to the body of the church until they have proven that they are worthy of at least living in a Terrestrial Eden.