There has been a massive dropoff of multiplayer games both on the Larian Discord, and in general. Looking at the concurrent players it also seems that the number of concurrent players is also dropping off as well as people turn their attention to other games.
At this point it doesn't seem like this is something recoverable - or at least if Larian spends the time and money to introduce robust modding tools that it will be relegated to a niche group that utilizes them.
I am disappointed we didn't get better multiplayer.
I think not including a couple small self-contained Modules that showcase the multiplayer capability of the platform was a significant lost opportunity. BG3 as a multiplayer module is not ideal - it's too long, sprawling and has too many cinematic hours to be an effective demonstration of the multiplayer capabilities of the game. A good multiplayer module doesn't need VA, or a lot of cutscenes. It doesn't need a main character or a central narrative - it just needs a place, problem and possible paths to a solution/resolution. A good example would be something like The Keep on the Borderlands, but there are SO many others to choose from.
DOS2 had at least the GM mode, strong modding tools and even came with an Arena Module for multiplayer battles.
BG3 had none of that. Long term viability of a product rests in it's multiplayer capabilities. However, you have to introduce those capabilities from the get-go and support them continually. It's one of the (many) reasons Elden Ring had such a long shelf life.
Maybe the next game Larian makes with the 5E system will have the kind of tools needed to sustain multiplayer gameplay. I think though for now the opportunity has passed for that to be a thing for this game.