When dot com companies failed, their work was thrown away or sold for pennies on the dollar to companies who ignored it. Decentralized systems built on Ethereum are forces of nature: they don't get shut down and don't depend on any group in particular for their functions.

Some products might be too early, but they'll just keep running with their small user bases until the market is ready. Companies should proceed with caution, but individuals who want to make an impact should start today.