The plane can only really support a small handful of missiles, nothing close to the Arsenal the Navy's F-18 used to be able to haul into battle. It's fast, sure, but that comes at a cost to fuel efficiency, so while infantry in remote Afghanistan can get air support in less time than a pizza, "one pass, haul ass" means that if the air strike wasn't perfect, they need to call in a second strike group and wait again, not to mention the immense cost for the first few jets and bombs.
The military is trying too hard to make a one-size-fits-all solution, when there has been one for close air support since Vietnam: the rugged and powerful A-10. In fact, with more and more of the fighters being forcibly retired, special ops teams are rightfully concerned, since they could previously rely on the A-10 to make 10+ passes before having to refuel, giving ground forces a significant advantage.
The moral of the story is that more tech, more cost, and more complexity does not always culminate in more value. We have become so accustomed to the notion that things will always get more advanced, and therefore better, that we have forgotten to look to the past to replicate the same success in the future.