I consider my husband and I to be a very common case - in an ideal world we would each have a personal account and share a joint account. (In reality we have many accounts because each one returns certain benefits, e.g. related savings products, good travel exchange rates, air miles, etc.)
A case few people seem to have made is the reality of running a household without a joint account. Almost all of the utilities are in my husband’s name (we do not share a surname) because he is the sort of person to get MSE emails and enjoys keeping our bills down and our finances in order. I am a stay at home parent and I am usually the one who has the time to monitor bills and speak to service providers when there is a problem. It’s difficult enough to do this when I am not the named account holder but impossible when I’m not named on the account the funds are coming from.
Also, it should be pointed out that a lot of Monzo’s investors and early adopters are men. Financial parity with my partner is really important to me and it really irritates me that in order to fully transfer our finances to Monzo, we would have to return to a 1950’s system where I ask him every time I need to move money around, and he has to effectively transfer a stipend into my account every month.