I found the question Why do many languages not support named parameters?
I saw that it has been closed as opinion-based. However, I would argue that this question is not really opinion based.
Is there a disadvantage of this that I'm missing? If not, why do many languages not allow this?
The question is asking about possible disadvantages, perceived by language designers, or their reasoning. Whether the perceived disadvantages or reasoning is relevant or not is opinion-based, but the question is not asking about that. Just about which possible disadvantages or reasoning that the designers happened to find relevant, which is not opinion-based. The question is in no way soliciting opinion based responses from answerers. As a comment there states, the question is more a matter or history than opinion.