Describe the bug

The initialization QiskitRuntimeService() becomes noticeably slower in 0.42.0 compared to 0.41.1.
I'm not sure whether this change is intentional.

Steps to reproduce

from timeit import timeit
from qiskit_ibm_runtime import QiskitRuntimeService, __version__

print(f"runtime_version={__version__}")
print(f"QiskitRuntimeService(): {timeit(lambda: QiskitRuntimeService(), number=1)} sec")
service = QiskitRuntimeService()
print(f"backends(): {timeit(lambda: service.backends(), number=1)} sec")

runtime_version=0.42.0
QiskitRuntimeService(): 2.605221999983769 sec
backends(): 4.723045916995034 sec

runtime_version=0.41.1
QiskitRuntimeService(): 0.0004281250003259629 sec
backends(): 4.443328083987581 sec

Expected behavior

0.42.0 is as fast as 0.41.1

Suggested solutions

Additional Information

• qiskit-ibm-runtime version: 0.42.0
• Python version: 3.13.6
• Operating system: macOS 15.7