"My view is that a ritual like kAsi yAtra could not be indicating going to saMnyAsa, as these dharma sutras should have been taught in the brahmacarya (in those days). Hence kAsi yAtra evolved more as a ritual identifying most learnt student out to go to kAsi for much higher learning,"
so announces Sri thebigthinkg at the end of his treatise.
Let me assume, for the sake of clarity, that he is not referring to the "marriage ritual" he mentioned elsewhere in this forum.
The Brahmaanda Puranaam urges us to adore the Paraa-shakthi with the naama: "loka-yaathra vidaayinye namaha". The Kali sahasra-naamaavali advises us to adore Her with the naama: "kaashi vilaasinee, kaashi-kshethra rakshana thathparaayai namaha".
He apparently does not accept these as encouraging members of all four aashramas to make voluntary pilgrimmages toi Kaashi.
He must be aware that on completion of his religious studies a brahmachaarin undergoes, with the permission of his gurus, very important samskaaram known as samavartana, which involves a ritual snaanam, before the graduate returns home.
In the circumstances, no question arises of only the "most learned student" going to Kaashi for "much higher learning". On the contrary, it is the disappointed householder, fed up with the responsibilities thrust upon his shoulders, to bear the burden of supporting the whole of society, that impels him to abandon his ties and try to escape to Kaashi seeking anonymity among the crowds there.
There is a Tamil song which I have heard mocking this trend:-
kaashikku pogum sannyaasi
un kudumbam ennaagum nee yoshi.
(hey, sannyaasi running away to Kaashi
give a thought to the plight of your abandoned family.)
S Narayanaswamy Iyer