“the first quantum processor where error-corrected qubits get exponentially better as they get bigger”
Achieving this turns the normal problem of scaling quantum computation upside down.
The scaling problem is multifaceted. IMHO the physical qubits are the biggest barrier to scaling.
In theory, theory and practice are the same.
Google's announcement is legit, and is in line with what theory and simulations expect.
“the first quantum processor where error-corrected qubits get exponentially better as they get bigger”
Achieving this turns the normal problem of scaling quantum computation upside down.