I am posting this news article because if I was about to travel to this area, I would want to be informed about this.
Here is a link to the local news (German). The rockfall occurred on Saturday, and there is still a lot of movement, 6 cm/day. If this continues, or increases, there is the possibility of another event occurring.
You can see from the map that it is not in the main tourist area, but rather the other side of the lake. They have been monitoring this area for years. It is not the first time that there has been a rockfall there and they continue to reassess the danger.
No one was hurt, but you can see by the Ticktock video that people were quite frightened by the noise and visible dust clouds created by the fall. They report that some of the boulders that fell were the size of minivans.
https://www.bernerzeitung.ch/felssturz-am-oeschinensee-3000-tonnen-fels-stuerzen-ab-901197012329