On the Temporality of the Torah

Isn’t it a bit annoying that a large part of the commandments and mindset of the Torah was relevant mainly or only in ancient times? It seems as if the Torah was given specifically to our ancestors back then. And if that is indeed the case, the Torah was given specifically to them, doesn’t that detract a bit from its general relevance to us? Why would a God who sees beyond time give a local Torah?
The validity of the relevant exegesis today is not what bothers me. What bothers me more is that most of the Torah (as I think) deals with practices that have long since passed, with pre-historic society and moral values, local folktales and one-off commandments. And what that says about the person who wrote it.
Of course, the question can easily be deflected with ad hoc arguments for the most part, but honestly, it’s annoying.
What do you think?
Thank you very much!