Does Monzo offer a joint account?

So, I know that there are many, many threads on this, but my question isn’t about the “how?” of the implementation, it’s more on the “when?”. There seems to be no mention of joint accounts on the Monzo Transparent Roadmap, which is confirmed by the blog post on The Year Ahead, 2018. Now, I know that everyone has their pet idea that they think is more important than all the other ideas, but I would like to argue that this idea is objectively very important - you only have to look at how many times it has been raised here (and those are just the times people have raised it as a topic, there are plenty more hits if you search) to see that it is a burning issue. In fact, no other issue (apart from what colour the cards should be) has more responses if you search the ideas category. While Monzo has opted to get other providers to manage major parts (mortgages, savings, …) of the traditional banking experience via the forthcoming marketplace, this isn’t possible with joint accounts - they form part of the core banking experience.

So, my question is: why on earth is this not anywhere on the roadmap?