His actions definitely slowed down Cardassian efforts to fortify their border with the Federation and their ability to launch an offensive strike.
How so? He destroyed two warships and one transport that may or may not have been contributing to the escalation effort. Hardly a devastating loss, considering what we later learn of the scale of the Cardassian military. And nothing in his actions was indicated to have the consequence of discouraging the Cardassians; to the contrary, at the conclusion, the villains of the week learned that Starfleet would not
inspect their shipments.
He may have only destroyed a few craft but he brought the entire area of space to the attention of Starfleet and the Federation. Plus he blew the cover on them using dampening fields on science and transport vessels.
Which is why the Cardassians stage their later attempt from Galorndon Core, nearly three years later.