We’ve come home through Paris and the Eurostar today (planned end of holiday). I was a bit nervous and we took a taxi to the train station rather than getting the local trains / metro but it was much less stressful than I feared - lots and lots of armed police around in Gare de Nord and they were being very cautious - checking behind things etc on every pass through.
Our Eurostar left on time but took much longer than normal due to using the slower speed lines. All felt fine on the train.