This was not really a "violent" incident, in fact the boats do not appear to have made contact at all. From what I can see it looks like the spinn sheet snagged on the leeward boat, fetching them both up to a stop. Some crew went for a swim, and it looks like the boats were tethered together for a time as the leeward boat seems parked for a bit.
In this particular venue; high speed, light weight
dinghies, really, it would be just another day on the race course. The fact that if was a light air day kept the carnage to near zero.
There would likely have been penalty turns or a protest ensuing, but I'm sure both boats carried on in the end.