We are focusing here mostly on the plant side, so I am using the title Pollination Botany rather than Pollination Biology or Pollination Ecology. The gymnosperms used wind as a pollination vector. Wind pollination could work for the gymnosperms because of where they live. These vast forests are a nearly monoculture of conifers. There are many individuals of the few species found in these forests.
Wind pollination can work in angiosperms too, where almost-monocultures occur.
An example are the grasslands and savannahs. Here huge stands of a relatively small number of species occur. There is plenty of opportunity for stigmas to be down-wind from anthers. Most grasses are wind-pollinated. Angiosperms that live in, say, a tropical rain forest cannot use wind pollination effectively.