But not higher difficulties... at all. Game is not built for encounters with large parties in the slightest. That would require rebuilding the entire combat experience from the ground up in a span of a few months.
I think this entire conversation is predicated on not enough information. If, as has been commented, this has been discussed before, we none of us know what Larian has (or hasn't) been doing in the background. it's best we don't get into an argument over something that we, none of us, have any facts about.
I'm not arguing? Having a larger party would be fun, but there are four things that have been consistently demanded by some members of the community to be met with absolute radio silence, which I consider the "Four Horseman of the Larian-Would-Never Apocalypse":
-Larger Party Size
-Day/Night Cycle (This one I am most upset about not having)
-Different party movement mechanics
-Real time with pause option
It's not that we don't have enough information. The fact that there are long-running megathreads going back for years without any attempt at implementation is evidence that these things are not being implemented (or are much lower priority). I'm happy to be wrong on release, but most signs point to "no." From an epistemological standpoint, there is much more reason to believe that we are not going to get these four things, and less reason to believe that we will. For those of us who have been watching the forum longer, there are facts to point to a lack of implementation, while there is no evidence towards any attempt at implementation.
Edit: Also, if Larian were considering rolling out a larger party, given how it would fundamentally change combat, they would likely want to test it on early access. The lack of the presence of something that would fundamentally alter combat at higher difficulties in the early access months before release date is evidence to non-implementation. Larian wanted to test reactions, so they put them in early access. Same with flight. And classes. But not a change in party size, even though that would fundamentally change the game balancing?