I’d quibble with Ancient Greek, as well. The inhabitants of Athens, Sparta, Epirus, Macedon, and Ionia all spoke varieties of ancient Greek (I’m not sure what is implied by spelling “ancient” with a capital “A") but I very much doubt if they all sounded even remotely the same, even if they were all reciting the same passage from, say, the Iliad.
Likewise, I doubt whether any 25th century English speaker would be able to tell very accurately how 20th century English sounded, if he/she were only able to compare the sound of the same words spoken in, say, Little Rock, South Shields, and Sydney respectively.
As for medieval Latin—are we to suppose that it would sound the same in the mouths of a 10th century Swedish, Irish, Venetian or Byzantine cleric? I’m just asking - this isn’t a rhetorical question. Whose medieval Latin do we know perfectly well the sound of? Was Roman or some other pronunciation the world standard?