To crack a single key using Shor's algorithm would require about $30k in energy with tens of megawatts continuously needed using estimates extrapolated from today's capacity. It would take 30 minutes to 8 hours with around 2500 logical qubits (estimated requirement to crack a key).

Those 2,500 logical qubits require approximately 13 million physical qubits due to error correction overhead. Current quantum computers only have 100-2,000 physical qubits. We're roughly four orders of magnitude away from this capability.

The most powerful quantum computers today have a bit more than 1000 physical qubits, and about 12 logical qubits. Physical qubits are doubling every 9-12 months.

Major companies project:
IBM: 100,000 physical qubits by 2033; 2,000 qubits by 2029
Google: Fault-tolerant quantum computer by 2029
Quantinuum: Fault-tolerant system with 1,000+ logical qubits by 2030
Fujitsu/RIKEN: 1,000 physical qubits by 2026

So they think we're still a half decade from being two+ orders of magnitude away from BTC being at risk. If it moves quickly we might see this around 2031-2034. A more pessimistic growth ramp puts it closer to 2040. Whoever does it will need to invest a ton of money into the computers and energy needed to crack each individual key. There will only be a few computers in the world able to do this initially and it's unlikely they'd use those resources to crack Bitcoin keys.

Why are people suddenly complaining about this now?