Emin Gün Sirer says the biggest long-term threat to Bitcoin may not be quantum computers or competing cryptocurrencies — but Bitcoin’s own reward system.
His concern is simple:
Bitcoin miners earn less and less over time because of halvings.
Every four years, Bitcoin cuts mining rewards in half. Miners still secure the network, validate transactions, and protect Bitcoin from attacks — but the amount of new BTC they receive keeps shrinking.
Right now, miners are supported by two income sources:
- block rewards
- transaction fees
Over the long term, Bitcoin is expected to rely more heavily on fees. The question Sirer raises is:
Will transaction fees alone be enough to keep miners profitable and the network secure?
Why this matters
If mining becomes too unprofitable:
- some miners could shut down
- total network security could weaken
- mining power may become concentrated among fewer players
Recent industry reports already suggest pressure is growing.
Some estimates say around 15% to 20% of Bitcoin miners may currently be unprofitable, especially operators with expensive electricity or older mining equipment.
Mining economics have become tougher since the 2024 halving, with production costs rising sharply while miner revenues have struggled.
Sirer’s idea
Sirer suggested Bitcoin could eventually use something like a “pre-consensus” layer to help reduce strain on the main network and improve efficiency.
But changes like that are controversial in the Bitcoin world.
Bitcoin’s community is known for being conservative about major technical changes, especially anything touching the network’s security or monetary structure.
Bigger debate
The discussion really comes down to one long-term question:
Can Bitcoin’s fee market eventually replace the shrinking block rewards that miners depend on today?
Some believe:
- rising adoption
- higher BTC prices
- and larger transaction demand
will naturally support miners through fees.
Others worry that the system could become less sustainable over time.
In simple terms
Bitcoin was designed so mining rewards slowly disappear.
Now the industry is debating whether transaction fees alone will someday be enough to keep the world’s largest crypto network secure.
