With the recent Vitalik Buterin's quick merge proposal, there is a possibility to deliver the merge sooner. The main advantage of the proposal is that it introduces fewer required changes to make the consensus upgrade on Ethereum Mainnet, i.e. replace PoW with PoS.
This proposal does imply that the Merge becomes the main focus of Ethereum core developers after London and Altair (the beacon chain upgrade expected to happen soon).
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