FWIW we just did this evening cruise on the Viking ‘Skirnir’ about a month ago. It’s a dinner cruise where the ship leaves the dock and then cruises up and down the Danube for an hour or so, before coming back to the dock for the night.
After a day of excursions the next day, it leaves for Amsterdam the next evening.
I was setting up on the forward terrace that night and saw a number of these small sightseeing boats cut across in front of the Skirnir trying to beat them underneath the Margit bridge, one of them so close in front of us that I could no longer see the boat at all.
That’s what happens when you play chicken with a 443’ long river cruiser.
The video looks like the smaller boat was minding its own business when the big boat willy nilly plowed into the backside.