I think it's pretty clear that the powers that be's minds were on Wano the very minute Whole Cake ended. Which…I mean, I completely understand. A lot of us here worship Reverie and the little sort of break it offers from the main plot, but this is an absolute nightmare for the anime. You have an arc that ties together elements that haven't been addressed in what's approaching a decade, then waits to give those elements payoff until AFTER Wano (with the occasional exception), which probably won't happen for another three years at least. Wano, on the other hand, has had the intention of being a golden goose arc for a while, even if much of the crowd here doesn't see it as such yet, its story has a ton of potential to draw in weekly viewers.
So honestly, I don't see how the anime was going to make anyone here happy. They had to extend the arc with flashbacks out of necessity to help it make sense to casual viewers, then for the sake of promotion couldn't afford any more time for filler arcs (though I do think it's silly that they are including Stampede filler, just not in between Reverie and Wano).
I haven't watched every Reverie episode on account of being busy, so I'm not sure about the overall quality of the arc production...but I what I said above does not excuse bad production, especially instances of bad art (which may be forgiven if Wano looks consistently good) or bad flashback pacing (though all the flashbacks I have seen so far, including the one in this episode, have been pretty well handled).
Good ol' Magnum Opus Dissonance.
Episode itself was okay, art wasn't great and the Sabo filler was rather suspect, Kuma stuff was handled well though.