Jagjit Singh questions A R Rahman's talent

https://www.youtube.com/watch?v=nemm-9sSplw

Jagjit singh ko singers ki badi parakh hai. I remember during a certain episode of saregamapa one singer was performing very well. But then Jagjit Singh gave him a song of his own choice and that singer faltered badly. Even the other judges were shocked who seemed to be very impressed with him till then.

However, here i kinda wonder that if A R rehman can be questioned about ghazal composition then even Jagjit Singh can be questioned about singing kishore kumar type or western based songs. Jagjit singh also stuck to a particular style only na?