Justin Drake, a researcher at the Ethereum Foundation, stated that Ethereum will soon become an "ultra sound" currency, while Bitcoin will be "eliminated" as it approaches its supply limit of 21 million, sparking debate between the two communities.

Drake recently stated in a post on X that to make ETH "super sound again, either the supply must decrease or the burn must increase. I believe both will happen."

Ethereum's supply will become deflationary after the merge in 2022, but its supply will begin to increase in April 2024 after the Dencun upgrade, as the upgrade reduces the cost and total amount of burning on the L2 network.

However, Drake compared Ethereum's supply to Bitcoin's supply and found that since the Dencun upgrade, Bitcoin's supply has increased by 655,000 coins, while Ethereum's network has increased by 462,000 ETH during the same period. At current prices, the former is worth about $63.5 billion, while the latter is worth only $1.25 billion. Drake said, "Today, BTC's supply is growing at a rate of 0.83% per year, 66% faster than ETH."

He also pointed out that Bitcoin's 21 million supply limit could pose long-term security risks, as miners' income mainly comes from block rewards (which accounted for about 99% in the past week, with only 1% coming from network fees). He added that because the cost of attacking the network is relatively low, Bitcoin is vulnerable to security risks.

However, analyst James Check stated that critics of Bitcoin's sustainability failed to consider factors such as energy progress, mining efficiency, and economic incentives. He said that if Bitcoin reaches a reserve state, high fees are inevitable, similar to the fees institutions pay to securely store gold.

He added that over time, network fees will cover operating costs, and subsidies have already covered capital expenditures. Check also believes that energy progress, especially the use of nuclear energy and wasted energy, will reduce mining costs.