It's on the small screen through the Disney+ series, Obi-Wan Kenobi, which is set a decade after Anakin and Obi-Wan had their falling out. The match of the century happens in Obi-Wan Kenobi episode 3, where Darth Vader easily overwhelms his ex-Jedi Master. Darth Vader avenges his revenge against Obi-Wan in the third episode of Obi-Wan Kenobi. With three more episodes of Obi-Wan Kenobi to go, there is a chance that their paths will cross again. It's clear that living and dying don't have that much of a difference for him right now, as he noted in Obi-Wan Kenobi episode 3. Lucasfilm decided to announce it immediately as part of the marketing of the series, along with the confirmation that the show would see the former allies battle each other.
There is a specific reason why Darth Vader allows Obi-Wan to go in Obi-Wan Kenobi episode 3 instead of killing him.
The tables have turned for Obi-Wan and Anakin a decade after the Jedi Master left his Padawan on the verge of death. He thinks that his former Jedi Master put him in a similar situation by keeping Obi-Wan alive.
Obi-Wan's survival in the series is guaranteed because of the events of the original film. Darth Vader is more satisfied with knowing that the Jedi Master will be in immense pain than he is with seeing him die. He allowed him to escape after burning him on the ground, but it was a sensible decision given the villain's ultimate plan. The Jedi Master and Darth Vader had an encounter in the Disney+ show. He decided to drag Obi-Wan through the flames because it would prolong his physical suffering. He has been living in isolation for a decade and is at the lowest point of his life.
Darth Vader was going to be in Obi-Wan Kenobi.
This is a more brutal way of torturing Obi-Wan. His quality of life wouldn't get much worse if he were nearing the height of his powers. The Jedi could have easily been ended by the Sith Lord. Even though he clearly has the upper hand, he chooses to drag their fight. Darth Vader is currently trapped in the same hell. Darth Vader does not want Obi-Wan to die instantly. The story for the Disney+ project underwent a few revisions. He's also reliant on his suit, which has its own problems. In Obi-Wan Kenobi episode 3, he says this himself.