EXP Share is Pokémon's way of allowing players to save time and energy by sharing the experience points gained in battle with all non-fainted Pokémon on a team, regardless of whether they participated in the battle.
The new Pokémon Sword and Shield games have modified the concept a bit controversially: they have eliminated the ability to turn this item on and off.
So is this good or bad? Is EXP share an 'easy mode' for the Pokémon games, and more importantly, does it make the series better?
The benefit of the EXP Share is that you don't need to grind excessively and waste time raising low-level Pokémon. This also makes it easier to evolve Pokémon and can help in completing your Pokédex. Newcomers can transition easily into the gameplay and complete the game, as not having to grind can appeal to people new to Pokémon games.
However, many argue that this item makes the game too easy- and they're right! Sharing EXP with everyone on the team means there is no need to battle with each individual team member to level them up. This also means less training before Pokémon Gyms, and Gym Leaders are easier to beat as a result. There is also less skill involved: you can add new Pokémon to your team and have them level up to the rest of your team in no time, without even needing to send that Pokémon into battle. Many players think that was a rewarding challenge of playing these games, and with the inability to turn the EXP Share off, the only option to replicate that experience is to only have one Pokémon in your team at a time (which can be pretty risky).
I like the EXP Share because it makes it easier for me to complete the Pokédex, especially with all the evolutions. With the addition of the Wild Area in Sword and Shield, players have plenty of opportunities to catch many different types of Pokémon at vastly different levels, so having the ability to share EXP points among party members makes building a team a breeze. Having a mandatory EXP Share that you receive automatically at the beginning of the game can also appeal to kids. I remember when I was a kid playing Pokémon, building a team before I received the EXP Share required me to spend countless hours battling with each of my Pokémon so they could be strong enough to defeat Whitney's Miltank (literally the worst). However, I think that players should have the option to turn it on/off so they don't have to carry only one pokemon at a time to avoid using the EXP share. Plus, your Pokémon could faint and you could lose all your money!
Pokémon Sword and Shield are out on the Nintendo Switch now.