I am a technological optimist in this sense: I believe that, if technology is used wisely, it can bring bring economic comfort and abundant leisure to everyone.
This sort of optimism was common in the early twentieth century. For example, Keynes wrote in his famous essay "Economic Possibilities for Our Grandchildren" that "From the earliest times of which we have record ... down to the beginning of the eighteenth century, there was no very great change in the standard of life of the average man living in the civilized centers of the earth." But now, because new technology makes production more efficient, "mankind is solving its economic problem," and "a point may soon be reached, much sooner perhaps than we are all aware of, when these needs are satisfied in the sense that we prefer to devote our further energies to non-economic purposes." When that time comes, "man will be faced with his real, his permanent problem - how to use his freedom from pressing economic cares, how to occupy the leisure which science and compound interest will have won for him, to live wisely and agreeably and well."
That seems to me to be an optimistic view of the future.
By contrast, today's economic conservatives say that new technology and economic growth will solve our problems, and they seem to have a fairly bleak view of the future. There will be series of problems - beginning with those we are facing now, such as global warming, traffic congestion, and peak oil, and presumably continuing indefinitely - but don't worry, because technology will come up with a solution to each of these problems before it becomes a disaster.
They have no vision of a better future. We just continue the same consumerism we have now, but on a larger scale, even though international comparisons have shown that we in the United States have gone far beyond the point where consuming more makes you happier. We will keep promoting waste, even when it is an economic burden: for example, we will defend sprawl neighborhoods where people cannot leave their houses without driving, even if it means that people have to spend 20% of their income on their cars.
Conservatives consider this optimistic only because environmentalists have an even bleaker vision of the future. At best, they call for austerity: we should all hang out our laundry on clothes lines to conserve energy, regardless of the nuisance it causes. As worst, they say that austerity will not work and we are heading for disaster.
Environmentalists need to recapture some of that old optimism of Keynes and to start saying that our lives could be much easier and much more satisfying, as well as more sustainable. We need to give ourselves the choice of working shorter hours, moderating our consumerism, spending more time on our families and our own interests, and learning how to occupy our leisure to live wisely and agreeably and well.