The war was not caused by "media hype". That may have gotten people psychologically hyped for a war, but that was not the cause.

The immediate cause for the war (in the sense that it is the official reason for the US declaration of war on Spain) was the bombing of the USS Maine. In the 100+ years that followed it's destruction, most historians have set aside the idea that it was either a) a Spanish attack or b) a self-inflicted attack by the US as an excuse to invade. At the time, however, many believed that the attack was perpetrated by Spain. Those skeptical of this simply went along with it.

As to why there is no restitution for Spain, the colonies themselves were in open rebellion (or had just had their rebellions violently quashed) when the US intervened (on what was believed to be a legitimate cause for war). The Spanish government had also crossed the Rubicon, so to speak, in terms of its relationship with the population of Cuba through the Reconcentración which forced the island´s rural population to move to urban centers, failed to provide food or adequate shelter, and then sat back as civilians died of hunger and disease in camps (with deplorable conditions) made specially to house them. Eminent American historian Louis Pérez Jr puts the number of victims in the tens of thousands, though others estimate even more. While this was a kind of 'final straw' separating Cubans from Spain, other acts against the civilian population, such as the massacre of theatergoers at the Villanueva Theater during the Ten Years War (1868-1878) (ie. Cuba's first independence war), and other excesses had already alienated much of the island's population to Spanish rule.

While the Reconcentración itself was especially awful, heavy handed Spanish policies to suppress rebellion in its overseas colonies were pretty common.

Some compensation was actually exchanged as a part of the treaty, as you'll notice in Article III here.

As they agreed to the peace treaty they would have shaky grounds, at best, for further compensation.

I would also highly doubt that Spain would press the issue in the 20th century since its abuses against its own population (during this and previous conflicts) would open it up to major claims for restitution by members of its own ex-colonial possessions, especially Cuba.

As the US frames itself as a 'liberating' force and its longstanding anti-colonial position within the Western Hemisphere, it is unlikely that they'd agree with the principles behind Spain's demands.

I'd recommend reading Louis Perez Jr.'s The War of 1898: The United States and Cuba in History and Historiography for a text specifically about that conflict and how it has been perceived by historians over time. You can also consult his book Cuba Between Empires, 1878-1902.