Altcoin won't survive more than 5 years if they don't have a strong cummunity to create an unlimited demand, because new projects are happening almost everyday and they're ready to replace a coin that don't have demand anymore. So, only the strong coins with high demand right now that will survive in the future
Why 5 years? If there is no demand for any coin, it can be considered dead already. It will stay at the corner of the any shit exchange with zero volume.