They missed the mark of a few lore points.

There has been precedent for racism against Romulans. Balance of Terror is one of the Romulans most defining episodes it's a Tos classic and it has a super racist navigator guy in it. He openly hates Romulans and when he finds out they kinda look like Vulcans he starts being shitty to Spock. Then there was also that Tng episode where one of the crew on the Enterprise lied about being part Romulan and they put him on trial for a bombing.

And there are Romulans working for section 31 already. There was a DS9 episode that set it all up where the whole plot was Bashir unwittingly getting a Romulan charged with treason. The chairman of the Tal Shiar turned out to be a section 31 agent and Admiral Ross and Starfleet Command were in on it.