They have titles, but assumed to lack an actual political power nor dignity.
In normal case, even if they are rich, they want to avoid getting into political confrontations. True they have the merchants on their side, but if nobilities brings in their allies and counter with trade policies, even the merchants would have to compromise in the end
Duke's household is still a Duke.
Its still only below the royal family, and if the head of that ducal family handles foreign trade, and might as well also be their official foreign diplomat.
And whatever trade policies the dumb nobles can cook means jack if they only trade with themselves, their bubble will collapse sooner or later unless they are fully more than self sufficient, cause the foreign market doesn't want to deal with them.
Any decent noble households that handles either grain or farm produce, mining and metalwork, crafts etc. that can capitalize on such a dumb local trade policy can take full monopoly of the kingdom's economy, wouldn't let past the the chance and definitely just do under the table deals for that sweet sweet tariffs.
And the Violets being the ones handling foreign affairs can double dip in it.
nah, make it 13, that way they can throw in one of those pointless beach episodes as filler.
Yes, yes of course, can't go wrong with giving more screentime to Serena's SERENAS.
You know what, make it 14ep, so we can also get a fan service scene of young Serena's FLAT JUSTICE.