For a decentralized system like Bitcoin, the IO is much more expensive than the CPU. One byte of extra data means transferring to and storing on all nodes. So saving the data storage is very important to Bitcoin.

In the transaction structure of Bitcoin, if removing the public key part in the transaction data, we may save nearly 30% of storage. The cost is we have to check the previous output to check the signature. But still it is worth to do the trim, cause the 30% data saving. (the blockchain data may be decreased from 30GB to 20GB)

Is it possible to do that?