It depends a lot when the victory would happen during the war.
But eventually, how well Athens did during the war really prevents a full-scale victory : several truces or peace attempts generally went about a negociated peace such as the Spartan proposal after the Argusinae; because the city couldn't really hope more than that without a decisive victory. Athens could prevent being severely defeated thanks to its navy, but can't hope scoring mroe than bright tactical victories (as Argusinae) against its opponents.
Arguably, the whole Sicilian Expedition was particularly...half-hassed doesn't cover it : wishful thinking and bad leadership is a really flawed cocktail.
More you look at it, more you want to call it Trierelion : The result was an awful lot of hoplites, light troops and ships being lost for Athenes and its allies/clients, and political turmoil at home.
Sparing Athens this farcical campaign, either at the benefit of non-intervention, either in a less important but less divided expedition, would really really help the city face Sparta in the second part of the war, maybe leading to a better negociated peace between the poleis : but Athens can't really hope crushing Sparta if their opponent doesn't commit the same huge strategical and tactical mistakes they did.
So, with a settled peace in favour of Athens (probably including Decelea) , you'd always have the risk of a third part of Pelopponesian War kickin it sooner or alter as nothing would have been resolved eventually, and the war would have an hard time being over as long as one of the hegemonies concerned isn't crushed hard and deep : I tried to point out really quickly why Athens had less chances for that : not only less strategically prone to, but having lost a lot of its prestige among its "allies" which provided her with a lot of supply and funds.
Eventually, it just goes down to whoever can win a long war of attritions, somehow interrupted by some truces, being understood that Persians WILL subside at least one side to prevent the rise of a strong aegean hegemony (which is likely to disfavour Athens). Basically, thanks to strategical advantages and thanks to political advantages (no less than the support and funds they traditionally percieved from Achemenids during the IVth century IOTL), Athens winning a clear and crushing victory seems really unlikely to me.