All changes and upgrades to the protocol should strive to maintain and reinforce these Principles of Bitcoin
- 21 million coins.
- No censorship: Nobody should be able to prevent valid txs from being confirmed.
- Open-Source: Bitcoin source code should always be open for anyone to read, modify, copy, share.
- Permissionless: No arbitrary gatekeepers should ever prevent anybody from being part of the network (user, node, miner, etc).
- Pseudonymous: No ID should be required to own, use Bitcoin.
- Fungible: All coins are equal and should be equally spendable.
- Irreversible Transactions: Confirmed blocks should be set in stone. Blockchain History should be immutable.
After the hard fork date all above mentioned points will be valid for this fork except point 1: supply of ~5,000,000 BTC instead of 21,000,000 BTC.
Therefore whales will still be able to accumulate large amounts of the limited
coin over time the issue the OP has a problem with will exist again
as odolvlobo states.
If someone wants to become a whale, so it is also possible here. But it will be very difficult as there won't be sellers with large amounts of Bitcoin.