The outcome will be closely watched, if mostly as a symbolic end to an era

Question

Just over three years ago, François Fillon was the favourite to become France’s next president. The case that wrecked the candidate’s chances—known, after his wife, as Penelopegate—went to trial on February 26th and is due to end today. The Republican ex-prime minister, who served under Nicolas Sarkozy, is primarily charged with misuse of public funds. He put his wife on the parliamentary payroll between 1998 and 2013 to the tune of over €1m ($1.1m) for work that prosecutors say she never did. He has denied wrongdoing, and claims to be the victim of a “trial by media”. Mrs Fillon and Marc Joulaud, his political associate, are also in the dock. The outcome will be closely watched, if mostly as a symbolic end to an era. Mr Fillon has already retired from politics. And shortly after his election Emmanuel Macron introduced a law that bans members of parliament from employing family members.

What does the sentence mean? Just in case it becomes a symbolic end to an era, the outcome need to be closely watched.

Answer 1

"Closely watched" means that the result of the trial will get a lot of attention from the public.

"...if mostly as a symbolic end to an era" means that the trial won't have much political consequence, since Fillon has already retired from politics.

You can think of the "if" in this use as a synonym of "although". It's a concession that the outcome will be symbolic, rather than consequential.