Today’s Market Leaders will be the First Block Producers of Future Blockchains

Many blockchains allow anyone to join the network and validate transactions, if this new participant has enough power or staked coins. The real problem is that we don't know the intention of the new nodes, and they can be malicious. Decentralization is problematic when it comes to upgrading. Commercial companies may prefer another approach - the one that allows them to run and upgrade their network, as well as giving them the opportunity to control the content written within the blockchain to avoid legal problems.