Earlier quoted context omitted.
No, they didn't assume a risk of "oh, let's just forget the whole debt thing, who cares about that stuff anyway".
Yes they did. Default is a real thing and that's the risk you earn a premium for taking. On equity the price of the asset can change, on debt you either secure it or charge a rate of interest that reflects your assessment of the risk. Hence the shitty rate of interest on savings accounts - your principal is guaranteed up to a fairly large amount so you earn less.
Lumping the two cases together is an unjustified equivocation.