I don't think it was glossed over. I think it's more of a case of trying to see Sabine as she is now. She blew off the ceremony and Ryder Azadi - I couldn't see the Sabine at the end of REBELS season 4 doing that. She's living alone with a Loth cat, and viewing Ezra's hologram message with a sense of longing. She put away her armor. Her training with Ahsoka ended, and it's unclear as to why. The storytelling has been subtly placing these things in front of us, but without beating us over the head with it. It was Sabine's encounter with Baylan that crystallized this for the audience.
I also think Sabine knows that she has put herself in danger, despite Baylan's assurances. Shin is not a fan. Sabine is put in binders. Does she have faith in Ezra? Ezra was instrumental to defeating Thrawn at the Battle of Lothal.
The title of this week's episode "Fallen Jedi" seems like it's potentially doing some heavy lifting. Does it refer to Baylan? What about Sabine, with her fateful decision? And of course there's what happened to Ahsoka. That ending was profound! Ahsoka finds herself in the WBW again. And while I'm not surprised that she encountered her former master, it absolutely raises questions. Is this where a Jedi's spirit goes when they become One with the Force?
I think next week will be incredibly enlightening. Dave Filoni is the director for episode 5 of this season, and he has a pattern of taking on directing specific episodes that will be pivotal over the course of a season. He directed the episode of The Mandalorian where Ahsoka came to live action. He directed the episode of The Book of Boba Fett that heavily featured Cobb Vanth and introduced Cad Bane to live action. And I suspect that this next episode will be the one where another character that has been a big part of Dave Filoni's history will finally appear. As for the plot? There seems to be a lot in front of all of the characters - Sabine is in jeopardy; Morgan Elsbeth is on her quest to Peridia; Hera's squadron was nearly decimated; and Ahsoka is "elsewhere". I think Jacen Syndulla's line of "Mom, I have a bad feeling" functioned on multiple levels about the level of jeopardy, as well as with Jacen's potential with the Force.