Sometimes things happen in movies that aren't 100% in service of the plot, or larger story arc. This is
not always a flaw. Often this is a
good thing.
Coming at a movie solely from the standpoint that "all these puzzle pieces don't fit snugly and the larger whole isn't maximized for efficiency" isn't necessarily invalid, but not every movie is trying to be (or should be) the
storytelling equivalent of a modular apartment, either.
Rogue One is a flawed film, absolutely. There are 8 Star Wars films and it's probably smack in the middle. I don't like it as much as The Force Awakens. But the fact the Star Wars movie stops down to do Star Wars stuff every now and again isn't an automatic negative, and I don't know why the hell it would be. The fact the 8th Star Wars movie asks you to have some sort of familiarity with Star Wars is an inherent fault that comes up about ankle-high on an Ewok.
"The movie doesn't work because hypothetical people who have hypothetically never heard of Star Wars are going to be so hypothetically dense as to not understand the fairly basic storytelling on display without first having memorized Wookiepedia" is a really specific and silly criticism to level, especially in the face of the 30 or so
way more valid criticisms you could level at the 8th Star Wars film in the series.