Politicians and the idiot public thinking it was possible.
Past examples of multirole fighters all started out as dedicated fighter aircraft with very limited ground attack, that had over time were adapted and modified for more and more advanced ground attack munitions and capabilities. The F-16 and F-15 come to mind here. The cost of that development came later on, and wasn't lumped into the initial aircraft development, so we got great aircraft for fighter duties, and then modified for fast ground strike.
Also, in the past, ground attack meant dumb iron bombs, rocket pods, and using internal guns which are all relatively cheap munitions that don't require anything more than a change of mode on the gunsight for aiming or just practice. While sensored munitions are less wasteful in terms of success, it means more cost per weapon used and target killed, but it comes back down to success/cost ratio and the cost of procuring the sensors (like the SNIPER pod) or integrating such systems into the aircraft.