Is public blockchain implementation scalable enough so that it could be maintained on each computer normal users and why so much of data redundancy?
Consider if a normal user has to do any transaction or others keeps on updating the blockchain the size of blockchain increases which in turn eats up computer space so how feasible is it for normal user to maintain this public ledger?
When we talk about storing a copy of the ledger on each contributor node, we mean the ledger that consists of just the receipts and data hashes of transactions, not all data. Which information is stored in the blockchain is determines the scalability of the system across some dimensions and it also allows understanding how users and the concomitant information is abstracted within the system. For storing data in a blockchain network, we have other solutions like using storage sidechains, storing the file on an off-chain database and use a hash pointer to assure integrity, distributed databases, and filesystems.
And finally, according to McKinsey report, Public blockchain has low scalability in comparison to private blockchains.
In general, to use a blockchain, a copy of blockchain is not required, only access to blockchain is enough. Only few nodes and miners keep the entire copy of blockchain. Others retrieve only content specific to them, which is usually taken care by the wallet software.
There are projects such as Cardano (ADA) which address some of the issues of blockchain, but are still experimental. For example, the ever growing size could be solved by pruning the chain.
