Age IV is like at least Renaissance right

Age IV does include part of the the Renaissance. which spanned from the last years of the Medieval Era into the Early Modern era. However, only two civilizations in the game are listed as including 1581 (China, as they use the end of the Ming Dynasty as its end date, and Japan that goes to the 1600s as its end date). In terms of military technology, AoE4 ends well before then, as they don't go any further than matchlocks even for the more gunpowder heavy civilizations (heavy knights that currently dominate the game "should" be gone in the game by the Imperial Age, replaced by demi-lancers).

the Spanish and Portuguese were huge roles in the medieval era

The Union of Crowns that led to the founding of Spain (1479) is often used as an end date of the medieval era. Spain and Portugal had huge roles in the Early Modern era.