Compared to Battlefront II (2005) Battlefront 2015 only had one era. There were nineteen maps in the 2005 game, while Battlefront 2015 only launched with five (though there were smaller variants of each for game modes that had smaller player count). In addition there was no single-player campaign in the 2015 game, while one existed in 2005 game. Even taking Battlefront II out of the picture, this is still a fraction of the content found even in DICE's own Battlefield games (Battlefield 1 launched with 10 maps and a single player campaign) or other contemporary shooters (Call of Duty), and it released at the same $60 price. I don't think Jim harping on Battlefront 2015 for not having enough content doesn't invalidate his argument, because that game was barebones without the season pass content.
The apples-to-oranges content comparisons from game to game don't really help or have much logic to it, especially when you're talking about a game whose modes span from air-only combat to massive scale 20v20 to tiny scale 6v6. BF2015 had a number of maps, but only if you were willing to consider maps across all the game modes (it doesn't help that most of the small-scale modes were garbage).
"This other game has 12 maps, why does yours only have 9?" Doesn't really make sense beyond a silly numbers game, nor does judging entirely based on map counts or character counts.
Consider the alternative -- "PUBG is a huge success and it only has 1 map -- why should Battlefront bother making 2 dozen maps?