Forgotten Realms is clearly the richest and most detailed and maybe the favorite by WotC but this could cause a little fed up, like a superpopular song that becomes "old-fashioned".
Dark Sun is the freshest and most original setting with its own style but it is like incomplete, the metaplot...
It seems it is working good and it has got a 82% positive reviews.
https://www.notebookcheck.net/This-co-op-strategy-RPG-just-hit-Steam-s-trending-charts-with-a-D-D-theme-and-82-positive-reviews.1193332.0.html
The original expression is "(él) sabe más que los ratones colorados" ( = he knows more than the red-colored mice) where the red-colored mice would be a sprite-like creature with a lot of culture or knowledge, or great cunning to get their way, with the shape of a red-haired mouse.
A new...
Again with ChatGPT.
The first image is an atropomorphic red-mouse. In D&D terms he could be a nezumi from Rokugan or a tari from Dark Sun. In Spain we say "he knows more than red-colored mice". It also could be an ordinary man suffering some bizarre curse in Ravenloft.
The second image is...
There is other point. I have just seen WotC accounts in Facebook and Twitter and they haven't published any post in more a year.
We are in the last days of the year and we know nothing about the first sourcebook what will be published in 2026 when usually we should know it six months before...
Fizban? The Dragonlance incarnation was "nerferd" after the events of the war of souls and this could be abducted to Ravenloft by the Dark Powers, but this could be a great risk because the deity can be more dangerous than Vecna, or at least this could help Vecna.
I don't remember Moderkainen...
We are in the internet age and people want to know as soon as posible, but I don't remember after 2000 a December where I can't know what will be the first sourcebook to be published in the next year. The calendar of future releases is important not only for customers but also for investors...