Well i think that a) even if you are a Republican it's not hard to keep your mouth buttoned for 24 hrs as a minimum b) if you are senior civil servant you swear an oath of loyalty to the Queen / King so understanding that voicing a Republican view is possibly a bloody stupid thing to do might not be terribly wise and actually just saying 'if you are a Republic, there's plenty of time for that debate in the weeks, months and years ahead so don't be a twat' is a sane tweet but it doesn't get enough clickbait.
As for the threats of violence. We look forward to the change of tact by OJ and his sympathy and support for JKR being his next topic of conversation as part of his condemnation of all threats for having different political views.
A cynic would however say Jones, is riding the clickbait train for his own self serving ego. Again.