If a country has enough money and resources, then yes a fleet could be build that would be more powerful than our navy. Since the US is one of the wealthiest nations on earth however, no one has been able to pay more on a fleet that we have on ours.
The US Navy is not indestructible, nor are its tactics beyond defeat. However, a fleet of ships built over 30 years ago will have to be very inventive to defeat even a small number of US Navy vessels. The detection equipment alone provides an excellent advantage for US forces. Compile this with faster ships and guns that shoot accurately at longer distances, and a fleet 30 years behind the US would have to get very lucky to get a win on the seas.
A fleet built over 30 years cannot be better equipped than the United States Navy. This is because the Navy has access to materials and reinforcements that civilians do not. In addition, advances in material technology in recent years would make the parts of the fleet built 30 years ago be irrelevant.
I do not believe a fleet built over 30 years is better equipped that the United States Navy. Technology is constantly changing and the United States spends too much money on it's military and especially, it's military equipment. A fleet with technology from 30 years ago can not surpass the US Navy.
If another country spends 30 years building a fleet, it wouldn't be better equipped than the United States Navy. Our country's naval force is nearly unrivaled in today's world, and our ships feature the most advanced equipment. With that in mind, no other country comes close to matching our power on the high seas.