Warning: SPOILERS for Superman & Lois Season 1, Episode 2 - "Heritage"
Superman & Lois intriguingly changed why the Arrowverse's Jor-El (Angus Macfadyen) sent his son, Kal-El (Tyler Hoechlin), to Earth with hopes that Superman continues the legacy of the Kryptonian people. Superman & Lois is a new vision of the Man of Steel where Clark Kent and his wife Lois Lane (Elizabeth Tulloch) are parents to teenage twin boys. The Kent family moves to Clark's hometown of Smallville, Kansas, in part so that Jordan (Alex Garfin) can learn to control the superpowers he recently manifested.
As Superman's birth father, Jor-El has been a major part of the Man of Steel's mythos for decades. The most famous versions of the doomed Kryptonian scientist in pop culture are the Jor-El played by Marlon Brando in Richard Donner's Superman: The Movie and the Jor-El portrayed by Russell Crowe in Zack Snyder's Man of Steel. Smallville's Jor-El, voiced by Terence Stamp and embodied by Julian Sands, is also well-known. Each version of Jor-El shares the same core trait: they knew Krypton would explode and they sent their only son to Earth, not just for his survival, but so he can gain powers in the light of Earth's yellow sun and become the hero the planet needs. But Superman becoming the father of a new Kryptonian race wasn't always part of Jor-El's plans.
When Superman & Lois introduced their version of Jor-El, a new wrinkle was added in that Kal-El's father also wants the Kryptonian people to continue via his son having children. Jor-El doubted that a union between a Kryptonian and a human could produce offspring that was properly Kryptonian, and the A.I. avatar of Jor-El was surprised when Clark brought Jordan to him at the Fortress of Solitude because he began manifesting abilities. Jor-El was visibly encouraged by the news, and he told his grandson, "Well then, it is possible for us to further our Kryptonian heritage after all. You, Jordan. You will be the one to do it." Unfortunately, after running tests, a disappointed Jor-El concluded that Jordan's human DNA is "too limiting" and what powers he may possess will be too minimal for him to ever be like Superman.
Curiously, Brando's Jor-El never seemed concerned with whether his only son Kal-El could have children on Earth. In Richard Donner's director's cut of Superman II, Jor-El was visibly unhappy when Clark (Christopher Reeve) slept with Lois Lane (Margot Kidder) in the Fortress of Solitude, and he was disappointed by his son's desire to give up his godlike powers for a human. Bryan Singer's Superman Returns continued the Donner films' story and Clark Kent's alienation and loneliness were the central themes of the film. However, Superman Returns also created Jason (Tristan Lake Lebeau), Superman's son with Lois Lane (Kate Bosworth). Superman Returns giving the Man of Steel and Lois a child beat Superman & Lois to the punch by 15 years.
In Man of Steel, Zack Synder and David Goyer introduced the concept of perpetuating the Kryptonian legacy via the Codex, which was embedded in the DNA of Kal-El (Henry Cavill). The continuation of the Kryptonian race was what drove General Zod (Michael Shannon), who wanted the Codex for that very purpose and to terraform the Earth into a new Krypton.
The idea of Jor-El himself wanting Superman to further the Kryptonian line, albeit with human hybrid children, is a new spin in the mythos. It's also one ideally suited to Superman & Lois, which is about family and what it means for Jordan and his twin brother Jonathan (Jordan Elsass) to be the children of the world's greatest superhero. But it's also a bit of a strange retcon for Jor-El to want Krypton to continue through Kal-El since any children he has on Earth can never be pure Kryptonians. If Superman was really meant to father a new Kryptonian race, he shouldn't have been sent to Earth alone. This is why Man of Steel's Codex was such a tremendous concept, but unfortunately, it seems to have been forgotten in the DC Extended Universe.