It appears that many Pokémon fans' wishes for an open world game are coming true with the upcoming release of Pokémon Legends: Arceus. While a truly open world game like Pokémon Legends: Arceus has a lot of potential to deliver something unique to the Pokémon franchise, it might feel a little strange because of its setting, which might not include the cornerstone mechanic of Pokémon gym battles.
Throughout the long history of the Pokémon games, the formula has never strayed too far outside of novelty spin-offs. Players usually capture Pokémon, travel throughout that game's region from town to town, and challenge each gym leader in order to earn the right to take on the Elite Four. The gym leaders are essentially boss battles that must be overcome before the player is able to advance the story and continue their journey to become a Pokémon master.
Pokémon Legends: Arceus, however, takes place long before the other Pokémon games, depicting a rather primitive Sinnoh region with untamed wilds. According to The Pokémon Company:
"The story unfolds in a long-gone era, before ideas such as being a Pokémon Trainer or having a Pokémon League even existed. All around, you’ll find Pokémon living wild in harsh environments that make for a Sinnoh unlike the region you may remember from the days of Pokémon Diamond and Pokémon Pearl."
From what's been shown, civilization only exists in small, isolated settlements. With "ideas such as being a Pokémon Trainer" not existing at the time, it would appear the familiar gym structure that dominates modern Pokémon battling would also not yet exist. This will admittedly feel strange, but it has a lot of potential to be refreshing.
Pokémon Legends: Arceus Doesn't Need Gym Battles
Although not much of the core gameplay loop has been revealed outside of sneaking through grass and throwing old-fashioned Poké Balls, it's safe to guess that Pokémon Legend: Arceus will have at least some kind of boss battles. A complete lack of gym battles is actually a much more interesting possibility than some archaic proto-gym battle set up. It would be a missed opportunity to try something new if Pokémon Legends: Arceus involved traveling to other old Sinnoh settlements and challenging the best trainer there.
Pokémon training and battling should remain a rudimentary activity so that Pokémon Legends: Arceus can feel like a different game in other ways than just its open world design. A greater explorable area has long been a requested feature for the series, but its more or less linear progression is not the only critique the series receives relating to its stagnancy. Creating a game around what appears to be the origins of Pokémon training in the Sinnoh region makes Pokémon Legends: Arceus Game Freak's best idea in a long time, if only for the fact that it's finally something radically different.
The fact still remains that Pokémon Legends: Arceus is a Pokémon game, so it has to involve normal Pokémon staples in some capacity. There will be Pokémon catching, training, and battling, but the overall game structure in relation to these is where Arceus has a chance to prove itself. Players have the chance to enjoy a massive, open world Pokémon game that doesn't involve gym battles. The gameplay of Pokémon Legends: Arceus should be molded around the setting, not the other way around.
UPDATE - 7/31/21, 2:07 PM ET: This story has been updated with a quote from the game's official website, as further evidence of the likelihood of gym battles being removed.
Source: The Pokémon Company