1 Samuel 3:1, describes a very similar dearth of prophecy. I doubt either Eli or Samuel were likely to have foreseen that within just a few years there would be dozens of prophets!
"Now the young man Samuel was ministering to the LORD under Eli. And the word of the LORD was rare in those days; there was no frequent vision." (1 Sam 3:1 ESV)
"1David and the chiefs of the service also set apart for the service the sons of Asaph, and of Heman, and of Jeduthun, who prophesied with lyres, with harps, and with cymbals. The list of those who did the work and of their duties was: 2Of the sons of Asaph: Zaccur, Joseph, Nethaniah, and Asharelah, sons of Asaph, under the direction of Asaph, who prophesied under the direction of the king. 3Of Jeduthun, the sons of Jeduthun: Gedaliah, Zeri, Jeshaiah, Shimei, Hashabiah, and Mattithiah, six, under the direction of their father Jeduthun, who prophesied with the lyre in thanksgiving and praise to the LORD. 4Of Heman, the sons of Heman: Bukkiah, Mattaniah, Uzziel, Shebuel and Jerimoth, Hananiah, Hanani, Eliathah, Giddalti, and Romamti-ezer, Joshbekashah, Mallothi, Hothir, Mahazioth. 5All these were the sons of Heman the kings seer, according to the promise of God to exalt him, for God had given Heman fourteen sons and three daughters. 6They were all under the direction of their father in the music in the house of the LORD with cymbals, harps, and lyres for the service of the house of God. Asaph, Jeduthun, and Heman were under the order of the king. 7The number of them along with their brothers, who were trained in singing to the LORD, all who were skillful, was 288. 8And they cast lots for their duties, small and great, teacher and pupil alike." (1 Chron. 25:1-8 ESV)