A few fathers make appearances in the Pokémon series, like Gen 3's Professor Birch, who is the father to either May or Brenden (depending on the gender of the main character), and Meyer from the Pokémon XY anime, who is the father of Bonnie and Clemont. Outside of characters like these, though, Pokémon has a distinct lack of dads. In the video games, the main character's mom mentions their father periodically, but his exact whereabouts are unknown in most stories.
Many Pokémon games start off similarly: The protagonist moves to a new town with their mother, who often explains they moved thanks to a missing father's job. The main character meets the region's professor, obtains a Pokémon of their own, and is then seen off by their mother as they begin their Pokémon journey. This often occurs just hours after moving. Once out in the world, the player can return home at any time to visit their mother, but their father never seems to make it to the new house.
Fans have shared many theories on Reddit about what happened to the dads of Pokémon and about why, after so many years, there has been no official explanation from developers. These theories include a Pokémon war that took the lives of young men throughout the regions, an ongoing war that has many fathers deployed, and a divorce or separation between the main character's parents. For Pokémon Sword and Shield, specifically, there is a popular theory that the main character's mom is a single mother because their father is never mentioned at all.
The Pokémon Games Only Show The Protagonist's Dad Once
There is one Pokémon dad who makes a proper appearance. In Pokémon Ruby, Sapphire, and Emerald, the main character's father is Norman, the Normal-type Gym Leader at the Petalburg Gym. He is technically the first Gym Leader the player should face, but he turns his child away until they have four other Gym badges accumulated. Norman doesn't ever show up in the protagonist's home and is never shown interacting with their mom.
While it has never been discussed by Game Freak, it's possible the reason there are so few dads in the Pokémon games is simply that they are at work or busy during the times of day the main character visits home. The "stay-at-home mom" stereotype was more common in the 1990s when the series began, so perhaps that trope carried through each generation, eventually being molded into a single-parent situation to better include modern concepts. Either way, the lack of fathers in the Pokémon series will likely remain a mystery.
Source: Reddit