"Balance of Terror" took place 100 years before Sela was born. If anything, Nemesis showed that regime changes on Romulus were commonplace, so what they did a century before would be irrelevant now.
That's entirely conjectural speculation on your part.
"Balance of Terror" did establish that in Romulan society good connections to TPTB can outweigh rank and performance:
DECIUS: Only in code, Commander. To inform our Praetor of this glorious mission.
COMMANDER: Your carelessness might have ended this glorious mission. You're reduced two steps in rank. Return to post.
CENTURION: Take care, Commander. He has friends, and friends of his kind mean power. And power is danger.
There is no reason to assume that this has changed by the 24th Century, on the contrary Sela's young age with her father being a general strongly suggests that little or nothing has changed.