Before I proceed, I like all kinds of music and I like all musicians - I try to learn from every one. You may call me a man with no taste discrimination
Here is Palghat Mani Iyer's interview in 1978 published in Hindu by a music critic MNM - It is a long article
http://www.carnaticcorner.com/articles/ptsmani.txt
We (my parents and ancestors) used to live in a house, a couple of houses away from Sri Palghat Mani Iyer (I could hear him playing Mridangam from our house) - Sri MD Ramanathan graduated from the same college where my eldest brother got his Intermediate (and a whole lot of friends and relatives)
A couple of points he has made that is relevant in this discussion.
Somewhere near the beginning he said
Mani Iyer listed three artistes with outstanding voices: Ariyakudi RamanujaIyengar, Chembai Vaidyanatha Bhagavathar and M.S.Subbulakshmi. He had playedfor the two men singers. They had sung straight to the audience for years and knew the art of relating themselves to their listeners and establishinga rapport with them.
Towards the very end
In a passing reference to contemporary vocalists, Mani Iyer said M.D.Ramanathan had wasted his gift of a very rich voice by deliberately goingin for an extremely "thaggu" sruthi.
Of course Palghat Mani Iyer's main prediction seem not to be true (given at the beginning)
The outlook for classical carnatic vocal music is bleak with not a single artiste available who can be counted upon as a hopeful asset. In fact, vocalmusic may soon disappear from the concert scene if the present trend of musicians to sing in extremely low sruthis in complete disregard of ht needto acquire compelling virtues of tone and timbre continues.