Now I might just be seeing things, but I have the feeling that some server-side steps have been taken to reduce morphing, at least in this specific area.
First, take a look at the videos of the Matterhorn I made in November of last year. The first video was taken with LOD 10 and the drone camera was zoomed in fairly heavily. I don’t remember the exact zoom value, so I will state that the next video was taken with LOD 10 and drone zoom 75 which is quite exaggerated to show off the morphing. Videos are taken at 1080p and encoded with the newest (and much improved) SVT-AV1 version so I recommend watching in fullscreen mode.
Plenty of morphing, and unfortunately the LOD flickering is still very much there, but notice that the Matterhorn shape change at 0:12 is less abrupt than before. I’m using the Pennine Alps discovery flight for these videos, and I distinctly remember having to set LOD to 400 for the Matterhorn to take the correct shape at the starting point of the flight, but this is no longer the case.
Therefore, I think that the newer Swisstopo mesh data has now been recompiled and is being used at all levels of detail, not just the higher ones as before.
Now the exact same situation with LOD 200. I might just be imagining things, but I recall the overall morphing looking way worse at that LOD level. Zoom level is still the exaggerated 75.
Now a more realistic scenario, LOD 300 and zoom level 50. Far from perfect, but also far from the morphing mess that I remember Switzerland used to be.
Same situation, but with ground textures disabled. We can see that while there is plenty of pop-in throughout, the transition between the different levels of detail seems to be a lot more graceful than it used to be, with less of a tendency for the terrain mesh to shift downwards as the LOD goes down. With ground textures enabled, most of these transitions are nearly invisible.
Is it perfect? No. Is it better? I think yes. More investigation is needed. Paging @balance11.