If its useless then why would people buy it? If its useless then why its still very known and used by many? If it's useless then it will never be on top leading currency that people bought in these days. Calling it as useless is not true because bitcoin has already showed its potential to dominate other currency such as fiat. Bitcoin has a great potential in every aspect as lots of people are adopting and using it now. Bitcoin will be good as gold or much expensive than gold in the near future as its very limited suxh as gold or any other materials.