My first high school offered only French & Spanish. For scheduling reasons, the half-dozen freshmen assigned to honors classes were assigned French, so that was my first language. The next year, I switched to another high school, which happened to offer German, but my parents & guidance counselor insisted I stick with French. The French 2 teacher was an over-the-hill literature teacher, whose Italian-American urban accent was so thick, you could barely understand his French, with even several Francophone kids getting confused by him. The next year, I was allowed to switch to German, but the final two years of high school I barely learned anything. What I know today of German has come more from stuff picked up reading history. I was admittedly an indifferent language student, but they just don't teach languages very well, with little to no speaking or listening, and that mostly due to the individual style of the instructors.
In my second high school, they required two years of a modern language and one year of a classical language, and you could take more years of Latin if you wanted. I believe Greek might occasionally have been offered as well.
Most of the language teachers I recall were primarily other subjects. A heavily ethnic Italian, who was primarily an English teacher, taught my 2nd year of French, and while the German teacher was the real thing, including being actually German, she was a pushover as a teacher, and also taught social studies. My Latin teacher was primarily social studies and also taught religion, was the sophomore dean and the faculty adviser for mock trial & debate clubs. Latin was WAAAAY down his list of priorities or expertise. The other main Latin teacher was the principal. Whatever the priorities appropriately given to Latin, the human capital really isn't out there to teach it on a wide scale, which I would consider a systemic flaw in education. I do recall that in my parish school, hearing about an anecdote a few years ago, where the high school's religion teacher (a lay woman) got in a lighthearted proxy argument with the Latin teacher (a priest), debating which was the more important subject. The religion teacher thought she had the edge, naturally enough in a Catholic school, only for the priest to tell his students that Latin is the language spoken in heaven, so all the religion classes would be useless when they got to heaven and were unable to converse with God. Fairly humorous if you knew the parties involved and could envision them saying those things, but what I found interesting was that they gave the Latin class to the priest, rather than have him teach religion. On the other hand, any parishioner dedicated enough to teach at the school with have sufficient command of theology to teach a high school class, while if you are going to teach Latin right, the priest is the best choice, as he is professionally fluent.

It's the little details like that, which, IMO, account for the superiority of that system. Whereas the more mainstream high schools made the language the secondary priority.