Is it really necessary to close interstates 10 and 12 from Lafayette to Slidell?

Just got to Baton Rouge after driving from Houston. My bad for not checking the road closures, but since it went up to the 40's today I didn't really expect anything to still be closed. I was a bit surprised when I got to Lafayette and was forced to exit. I would have thought a road side sign would have warned me earlier, like those large emergency ones in Lake Charles. It wasn't too difficult to get here because I just took 190 instead. I don't really understand though how the 190 bridge over the Mississippi can be open and it looks like even the Lake Pontchartrain bridge is open, but all the interstates in Baton Rouge and New Orleans and everywhere in between are closed? I felt bad for all the miles of tractor trailer truck drivers I passed stopped on the sides of the highway.

Edit -

Just looked at the photos. Those do look pretty bad. I was in Houston the last couple of days where there were the same conditions. The interstates were clear by the afternoon today, but looks like it was slightly warmer there. When I checked in the hotel here this evening, the guy at the front desk was complaining about the shutdowns, so I assumed it was overkill based on how clear 190 was on the way in. I spoke too soon it looks like.