Of course it's a problem for Larian to solve. It's a problem for every developer who makes an RPG that has companions to solve. Come on, imagine if Larian (or any other developer) approached other problems that way, just doing the same obviously dumb things because fixing it isn't their problem. That's what Bethesda does, and no one should be emulating them.
The point is: it is a recurring problem for all party-based CRPGs. In that respect, it is very similar to being able to carry two department store's inventory around as loot, in your invisible back pocket. Like a party size cap, it is considered a necessary gameplay mechanic. And likewise, no-one has bothered to come up with a reusable explanation. I'd say: let the masterminds behind the D&D franchise come up with good explanations, instead of thinking up bunny people and turtle people.
Originally Posted by jono11
Also, there are easy solutions that take zero intellectual rigor:
1) No party size limit, balance the game for full parties and let players live with the consequences if they don't want a full party. 2) No party size limit, combat difficulty and skill check difficulty scale with party size. 3) Party size limit based in some way on Charisma or a similar stat. 4) Just don't have more companions than you want people to play with! If you really think good adventures only happen when you have a group of four people, then just don't have me meet more than four people! And don't tell me that limits player choice, because you're already limiting player choice by insisting that I only have three companions.
Those solutions might take little intellectual rigor, but they also don't meet requirements the game developer is likely to have.
