Thankfully I found an older LOD comparison of the Matterhorn I had made, which makes it easy to see how big the improvements are. Top is January 2022, bottom is June 2022.
Previously at the starting point of the Pennine Alps discovery flight the Matterhorn looked as if it was sliced in two at lower LODs, and it needed almost LOD 300 in order to assume its correct shape. Now it does not look totally unrecognisable at lower LODs anymore, and in fact just LOD 105 is enough to make it look good from the starting point.
Further studying the differences between my old and new screenshots, I can see that the LOD tile mismatching (causing seams in the terrain) and the shifting of both the mesh and ground imagery has been greatly reduced, supporting my theory that the lower LODs have been recompiled.
As a result, in regards to the morphing, flying around the Matterhorn at LOD 150 is more enjoyable than LOD 400 used to be. It is not completely perfect, but honestly it feels as good as it was before the first USA World Update back in November 2020, even with the high-detail mesh. If they could roll out these improvements to the entire world, it would be absolutely brilliant.
I checked Mount Rainier to see if there had been any improvement with the second USA World Update and unfortunately it’s still the same morphing mess, which is a shame because it looks really beautiful. I will be checking Norway next.