This is just a quick food for thought.
During Pentecost the disciples spoke in every language.
For a while Latin served as a way to speak to all the nations.
It still does, but what Vatican II realized was that the vernacular was needed to continue to speak to every nation well and with force. Many no longer spoke Latin or even understood it even in academic circles. What the Churched used to reach as many people as possible, was no longer reaching many people at all.
Thus, we can thank Vatican II for recognizing that the vernacular was needed, while Latin could also be kept and preserved. Thus, all could be spoken to.
(Vatican II loved and respected Latin – see this other post – it just also wanted to introduce the vernacular)