I disagree that it's just being pedantic. Calling it BG3 does imply some expectations of gameplay. If final fantasy tactics was called final fantasy 8 it would have left a lot of people disappointed and frankly mislead. If a studio made Half life 3, but it played like call of duty or borderlands (even set in half life universe), it would not be what people wants or expects, even if the game in isolation is fine.
Newer final fantasy games have made drastic changes to the formula as far as game mechanics go. Same goes for resident evil games and actually many other Japanese games.
