Some time ago it was common for children to be taught Latin. This is no longer the case. Most people don't think about why. Of course, Latin is a useless dead language; reading it is not a marketable skill, so teaching it is a waste of time.
However when pushed many people will admit that much, possibly a majority of what is taught in secondary school is ultimately not marketable. Literature isn't, except for a small number who will become authors or academics; the same is true of Latin. For that matter, the vast majority of people will never become fluent in, let alone work in, a "live" foreign language. Much more time is wasted providing language instruction that will never be used than would be lost by the small minority who need it learning as adults.
When pushed further, most will nonetheless defend Literature and Spanish instruction, usually with mystical justifications that appeal to higher values and the good life. But why is not a knowledge of Latin something with higher or intrinsic value? Why is knowing it not also a part of the good life?
Another argument is sometimes made against Latin instruction is that it is associated with the pre-1945 conservative tradition, and teaching it to children may therefore promote the values of that tradition. The person making this argument of course believes that those values are bad. This is the only argument that seems to me at least logically consistent, but it is also morally weak. If we eliminate Latin instruction because its main purpose is to transmit cultural values, which some may not approve of, why not eliminate all subjects whose main purpose is to transmit cultural values, since not everyone approves of any value? And if the cultural values that ultimately shape society are transmitted by what is very close to a state monopoly mechanism, can we truly say that we live in a free democracy?