Superman & Lois' cancelation marks the end of a DC era that spans 72 years and over six different actors who portrayed the Man of Steel on the small screen. Despite its ratings and popularity, Superman & Lois is ending with season 4, Nexstar's acquisition of The CW has brought many logistical side effects, causing dramatic changes in all the channel's shows. Superman & Lois' main cast was on board, and the show still had all the narrative potential to continue for at least two more seasons, but budget cuts and major changes in direction behind the scenes have led the show to a premature ending.
https://screenrant.com/superman-and-lois-cancelation-superhero-tv-full-circle/