A few points...
At flightaware it shows the max altitude of about 3200ft and 194 kts so they were probably clean when they hit the birds. The next swipe shows them descending.
Engine cert requires the engine to chuff a bird, water and ice but not BIRDS and with this on the fly-way, it may have been a flock. Contemplate throwing construction bricks in a cusinart... one blade goes.. another and then you have little to no thrust.
This was NOT a planned ditching so max kudos to the FAs for getting everyone off. I can't remember the last time I did a ditching scenario in tng.
The 320 is FBW which, as someone noted, means with envelope protection, NO stalls unless it went into direct law. Thus, no nose drop when it ditched and thus a less chance for blunt force trauma injuries.
Finally, no one on an inland flight listens to the briefing, especially the one about the life jackets. ERROR.. as this event proves.
Well done to the crew.. the entire crew and also to the rescue boats who were on the scene quickly.