A language carries its philosophy inside the words. Not all philosophical concept can be easily translated in other language. Take a Hindi/Sanskrit word "Aatma/Ātman" for example, it is translated into english as "soul".
But it is wrong translation as plant, animal don't have "soul", while even bacteria have "Aatma/Ātman".
If Sankrit is lost then the concept of "Ātman" will also be lost.
This number is vastly exaggerated. Porus was small king of a minor principality( modern day equivalent of a district).
References:
Ancient India : By R C Majumdar,
Wonder That Was India : By A.L.Basham.
I have only hard copy of these books. I don't know if e-book is available or not.
I may or may not have direct experience with this but I can comment on this part: "I would be in competition with others who've been practicing their trade for many years. It feels as if it's too late."
You will be pleasantly surprised how motivated learning of one month triumphs over years of experience of people who are just getting along with the job. If you have passion for any skill then you are already ahead of most people.
So " Efforts taken at this point to turn things around would be futile" is wrong unless its half-hearted effort.
I don't know about going back to school but I can definitely say: Full-hearted "efforts taken at this point" not be futile "for picking up a new skill" unless the skill is physically demanding.