From your screenshots, it appears that the optical density of the clouds has increased. I wrote a post last year where I used the custom weather tool to experiment with how MSFS draws clouds. Here’s a link to that post if you’re interested:
My tests last year suggested that the low optical densities in older versions of MSFS were producing clouds that were too thin (with the sun still visible through an overcast cloud layer, for example). Based on your screenshots, it looks like they have increased the optical density. Using the current weather system, I don’t think there is a perfect solution to this. Either the clouds will be too translucent, allowing a pilot to see the ground from deep inside the cloud, or they will produce this overly dark occlusion at the cloud base like you showed in your screenshots. Any improvement will require Asobo to make a more fundamental change to how the clouds are rendered, rather than simply tweaking the optical density parameter.