Yes, but that "something else" is designed (both via architecture and training data) to predict the language response from humans of language used by humans to communicate with humans, so addressing it like a human addresses a human doesn't just work well coincidentally, but by design.
I don't think that this is especially beneficial for the LLMs, the benefit of chat interface is that humans are social animals with lots of experience forming prompts like this.
There is an alternative that I've found has tradeoffs, where you give it its instructions in third person, e.g. 'Sam is an intelligent personal assistant. The following is a discussion between Sam and Max --- Max: [question]? --- Sam:' You tend to get slightly more coherent responses with that format, because you've hooked into the part of its mind that knows how text looks in textbooks and guides, which are usually well-edited. However, it often gives more 'dry' responses, because you've moved away from the part of its mind that's familiar with human-to-human forum RP.
Implies that the system's behavior isn't only controlled by the prompt, but by how you ADDRESS the prompt. So, start believing that it's a person and address it as such, and it's going to lean towards engaging with you as if it is a person, further misleading you.