Already, due to intense research effort and interest from the community in blockchain technology, answers to various challenges have started to emerge. For example, the concept of state channels has been developed as a response to scalability and privacy issues on the blockchain. Using state channels, the Bitcoin lightning network and Ethereum's Raiden are already almost ready for implementation.
This is work in progress, however and updates are available here https://github.com/raiden-network/raiden/milestones.
Moreover, various blockchain solutions emerged, such as Kadena, that directly addressed the confidentiality issues in blockchains. Other concepts such as Zcash, CoinJoin, and confidential transactions ...
