Part of the issue is irreversible transaction.
It would be safer to build a decentralized platform on top of Bitcoin where Bitcoin transactions can be reversed if unauthorized people gain access to users coins
You don't know what you're talking about. This would mean that anybody could reverse his transactions for no good reason. The merchants would have no reason at all to use Bitcoin, actually, it would be the opposite: they would avoid it.One of the ways to do this:
A decentralized platform could offer a reversible transaction service for funds that can only be sent to a multisig address before reaching its final destination. This should enable people with huge amount of Bitcoin to only send their coins to such addresses controlled by them and co-signers. Once a multi-sig address receives such fund the owner is immediately alerted and he can then authorize the transaction and the fund automatically sent to the final recipient. If the owner reject the transaction the coins is sent back to his address
some people thought you were trying to promote a CSW protocol breaking money steal/refund option.. breaking bitcoins immutability
however the multisig option you now describe is how some have done things in the past.. its called escrow