This is a great question to consider in relation to this famous Ode. Of course, it is the fifth section of this poem which contains Shelley's desire or purpose for writing this poem, as Shelley implores the West Wind to identify so strongly with himself that it will blow his thoughts and ideas all over the universe just as the West Wind blows leaves all over the place so as to initiate a "new birth":
Drive my dead thoughts over the universe
Like withered leaves to quicken a new birth!
And, by the incantation of this verse,
Scatter, as from an unextinguishd hearth
Ashes and sparks, my words among mankind!
Shelley therefore imagines his words acting as "The trumpet of prophecy" to the world, which he sees as being "unawakened." We can definitely describe him then as optimistic, because he believes his thoughts have the capacity to have this impact on the world, and certainly the fact that this remains such a recognised "classic" in part shows that this optimism was not misplaced. However, at the same time, we could also argue that this poem shows significant escapsim, and perhaps arrogance. Shelley seems to cast himself as a saviour figure upon whom the salvation of the world depends. His goal is nothing more than changing the world, and it is a real flight of fancy to think that one poet's words can impact the entire world and change it.