//Since Kanchipuram was their capital, the Pallavas must surely have built palaces there. But the reason why we find no palaces there today is because their palaces were made of brick or wood and not of stone. So, they must have been destroyed when invaders had attacked.//

One of the reasons i have ever thinking about is this mystery. In the places like urayur, kanchi, thanjavur where those kings have lived and had built many palaces. But why nothing is seen now but those temples have existed. One of the reason might be as u had given here other might be as those are religious and considered sacred, nobody wanted to touch. It is the army of the invaders which used to destroy palaces. Mostl Most of the the king who were artistic, would have ordered his army not to touch these artistic temples and chitrakudams but will order to fire the palaces where the enemy kings used to live. When narasimha varma pallavan raided vadhabi (somewhere north karnataka, reason is to avenge pulikesi II’s invade of kanchi and killing of his father mahendra varman), he ordered his army not to touch vadhabi cities aristic creatures but he didnt show mercy towards the city’s jewellery and pulikesi’s palace. His thalapathy, the great paranjothi (who later became siruthondar nayanmar) also took only a ganapathy who is later called as vadhabi ganapathy) and didnt touch any wealth. smilarly after narasimha varama pallava’s period, revenge from chalukya had ruined kanchi but they also didnt touch kanchi’s artistic things.

Also from the book, A Forgotten Empire Vijayanagar Kingdom, it is known that they have protected the temples of kanchi and others. Also through the defated hoysalas, malikafur invaded madurai pandya kingdom and these two battled at trichy. Because of fate (poor water supply, not having proficient armors etc), pandya lost the war, trichy and madurai were victims of these war as they are governed by pandyas. During this time vijayangar kingdom had started raising the power and watned to drive out mughals and got the control of mysore and kanchi. Also malik kafur got heavily weakened by the pandyan army and dont want to go with any other war, he is left no choice but to return to delhi. So kanchi and other northern TN temples were saved.