BTW My son is currently teaching his three year old son Latin.
Latin is a useful language to learn in the study of those languages descended from it, and even English which is not. Knowledge of Latin roots typically means one can decipher the meaning of words never previously encountered, in my experience. Certain career paths and disciplines almost require an understanding.
So, it’s not entirely dead and not exactly useless. I do tend to join you in being suspect of resorting to the use of Latin too often, though. It comes across as an attempt to obscure, or like the use of jargon to befuddle those not belonging to this or that in-group.
I am glad that your grandson is learning Latin. From there he will be able to learn almost every other Western European language except for German, Czech and Slovak.
“Catholics use it here where they are up to no good”.
Now that’s funny and sad simultaneously.
Fear not.
-Theo