Why is Edmund Spenser called "the poet's poet?"

Edmund Spencer, poet, is considered to be one of the best poets of his era.  He was a leader in prose and style transitioning into fantastical allegory with the poem The Faerie Queene. 

Spencer wrote one of the most famous Epithalamions, a prose or poem written for a bride, on his wedding day for his own young bride.

He was very anti-Irish and often wrote in a manner that allowed him to mask  his political intent to do away with the Irish.  Because he was not afraid to speak his mind and express himself through his poetry and his great talents allowed his words to flow with elegance, wit, and beauty, he is considered to have been well liked and respected by the poets of his day.  Even in death "The poet’s poet" was carried to his grave by poets and pens were thrown atop his burial casket in his honor.

He is known for his quotes such as;

"a poem for a song" which he created after being rewarded poorly by the government for his poem  "The Faerie Queene." 

"reason for the rhyme," which is believed to have been changed to "rhyme nor reason."