In addition to what you've said, I feel it doesn't jive with the scene where Obi-Wan meets Luke and R2. "Now that's a name I've not heard in a long time. A long time." isn't just referring to his literal name, at least in my opinion. In Rebels they conveniently avoid referring to him as Obi-Wan to keep continuity, instead having Maul and Ezra refer to him as "Kenobi" or "General Kenobi". But I feel that kind of misses the point. The name represents Obi-Wan the famous Jedi hero, as opposed to Old Ben the hermit. So the implication is that he put that persona behind him and he's been living a quiet life as a hermit. He's surprised that Luke mentions it because no one has called upon that aspect of his life in forever, and it provokes distant memories. Then Leia's message shows up, begging him to take up the mantle again, which is when he decides to embrace being a Jedi again. In that same scene he says he was once a Jedi, not that he is, reinforcing that idea.

To have characters like Vader duel Obi-Wan within the time period of his exile kind of removes that implication, making the scene more literal. It makes his heroic days feel less like a distant memory, and it means that Leia's hologram is no longer his first call to action since his golden years. I feel that's a weaker story, so Vader dueling him in the new show doesn't excite me at all. I'd rather see a something with smaller stakes. A more character driven show, not a "rollicking adventure." I'd rather the conflict be internal than some external threat like Vader or Inquisitors.