The main benefit is that it is constant. Languages evolve and meanings of words change over time. Latin, a so-called dead language has stopped evolving.
The Latin Mass therefore remains a constant and a common unifying experience for all Catholics world wide, conveying a timeless message and uniting us not just with each other, but with all Catholics of all times.
Latin might be a so called dead language but it must translate it into the many different languages to be understood. The words themselves don’t have any power in them. Saying words most people don’t really understand can’t give a common experience. The common experience must come from God regardless of the language.