I don't know that they stink, but you are not wrong. The only thing that is guaranteed is that if Romano [or Robertson] is on the mound blowing a playoff lead in the 6th inning of a post-season game people will go absolutely nuts, whereas if it's a trade deadline guy it will just be, "oh well, that didn't work out."
But they may also still prefer to trade for a controllable reliever not just for the deadline but going forward. Trading a few prospects might still be better than signing a reliever to a more expensive three-year deal or repeating a Kimbrel or Romano type deal where you save $ and years. At that point you are saying the prospects are worth less than the cash, which would be true [the salary control is worthless if they don't work out].
What Robertson lets you do is go big or go small, and probably no reason to go small unless someone is taking Romano or Ross's salary off your hands as with the trades last year.