Monzo’s ads can be smarter than that though, at least in some instances.
For example, they can definitely tell you that you would save money by buying a monthly travel pass from TFL, rather than paying for your travel on an ad hoc basis, based on your spending history. Then, offer you a loan so that you can buy that season pass straight away & spread the cost in installments.
I would have no problem with that sort of advertising at all, in fact, I’d welcome it.
If the analysis can be made smart enough, then you could even argue that they should be called something different than advertising & instead, they’re ‘insights’ / ‘recommendations’ / ‘suggestions’ etc.