I can’t find any instance where a prophet, other than Joseph Smith, saw the Savior. Since many of the prophets from the Bible and Book of Mormon saw the Savior, as did Joseph Smith, isn’t important that other prophets have seen Him?
Prophets have many roles. As their name denotes, they may prophesy the future; they reveal God’s message to His people; they may perform miracles in His name; they teach and witness of God and Christ. Please note that while these are things prophets have done, they are not all required in the calling. As Jesus’ disciples observed, “John [the Baptist] did no miracle” (John 10:41), but there was no greater prophet born of women (Luke 7:28). The core thing prophets must do is witness of Christ (Jacob 7:11).
As you note, many prophets in the scriptures shared their experiences with seeing Jesus. What you failed to note is that we don’t have a record of a steady stream of open theophanies every 5-10 years (which would be required to match our current prophetic rate). In the opening of the Book of Mormon, we have a record of Nephi and Jacob who saw Jesus (2 Nephi 11:2). Lehi saw him as well, but we don’t have his record (1 Nephi 1:8). Then we come to Enos, who hears the voice of the Lord (Enos 1:10) but does not see Him. So in 238 years (Jarom 1:13) we have 3 prophets who saw Christ and 2 who do not record such, along with prophets (plural) who may or may not have (see Enos 1:22 & Jarom 1:10-11).
President Hinckley shared with the world his experience with the voice of the Lord by sharing the experience of the biblical prophet Elijah.
“Mr. Wallace: ‘The Mormons, Mr. President, call you a “living Moses,” a prophet who literally communicates with Jesus. How do you do that?’
“Reply: ‘… I think the best way I could describe the process is to liken it to the experience of Elijah as set forth in the book of First Kings. Elijah spoke to the Lord, and there was a wind, a great wind, and the Lord was not in the wind. And there was an earthquake, and the Lord was not in the earthquake. And there was a fire, and the Lord was not in the fire. And after the fire a still, small voice, which I describe as the whisperings of the Spirit. Now, let me just say, categorically, that the things of God are understood by the Spirit of God, and one must have and seek and cultivate that Spirit, and there comes understanding and it is real. I can give testimony of that.'” (This Thing Was Not Done in a Corner, October General Conference 1996).
God’s plan for His prophets, teaching them to hear His voice, is the same that He has for all His children. And just as faithful saints have seen the Lord (as promised in John 14:21), so have prophets. President Lorenzo Snow shared with his granddaughter an occasion when he saw the Lord in the Salt Lake Temple. From her account:
“In the large corridor leading into the celestial room, I was walking several steps ahead of grand-pa when he stopped me and said: ‘Wait a moment, Allie, I want to tell you something. It was right here that the Lord Jesus Christ appeared to me at the time of the death of President Woodruff. He instructed me to go right ahead and reorganize the First Presidency of the Church at once and not wait as had been done after the death of the previous presidents, and that I was to succeed President Woodruff.’
“Then grand-pa came a step nearer and held out his left hand and said: ‘He stood right here, about three feet above the floor. It looked as though He stood on a plate of solid gold.’
“Grand-pa told me what a glorious personage the Savior is and described His hands, feet, countenance and beautiful white robes, all of which were of such a glory of whiteness and brightness that he could hardly gaze upon Him.
“Then [grand-pa] came another step nearer and put his right hand on my head and said: ‘Now, grand-daughter, I want you to remember that this is the testimony of your grand-father, that he told you with his own lips that he actually saw the Savior, here in the Temple, and talked with Him face to face.'” (as cited in Teachings of the Presidents of the Church: Lorenzo Snow, Chapter 20: The Kingdom of God Moves Forward).
Why did President Snow not share this witness with the Church? I don’t know. I suspect because he felt the sacredness of it meant that it was not for the world or the saints, but only those whom he felt prompted to share it with. While Apostles of the Lord have the charge to get this witness, it is their stewardship to determine how to share it. Elder Packer has shared his witness of the apostolic testimony borne by his peers.
“Occasionally during the past year I have been asked a question. Usually it comes as a curious, almost an idle, question about the qualifications to stand as a witness for Christ. The question they ask is, ‘Have you seen Him?’ …
“I have not asked that question of others, but I have heard them answer it — but not when they were asked. They have answered it under the prompting of the Spirit, on sacred occasions, when ‘the Spirit beareth record.’ (D&C 1:39)
“I have heard one of my brethren declare: ‘I know from experiences, too sacred to relate, that Jesus is the Christ.’
“I have heard another testify: ‘I know that God lives; I know that the Lord lives. And more than that, I know the Lord.’
“It was not their words that held the meaning or the power. It was the Spirit. ‘… for when a man speaketh by the power of the Holy Ghost the power of the Holy Ghost carrieth it unto the hearts of the children of men.’ (2 Nephi 33:1).” (The Spirit Beareth Record, June 1971 Ensign).
The latter-day prophets have all fulfilled the duty of their office to bear witness of Christ. Whether their knowledge came from an eye-witness like Joseph Smith or Lorenzo Snow had, or whether it was merely (ha!) from the still, small, voice, they have borne testimony of the reality of the resurrected Christ and the work He continues today. They speak God’s words and God’s warnings. It is imperative that we gain a similar witness and heed the voice of the Lord given through them.