Why does op-amp output impedance / parasitic input capacitance pole cause a noise peak?
When circuits have peaking, the noise is naturally also amplified.
Capacitance on Vin- will interact with the R_feedback, causing phase shifts. If the opamp is already of low phase_margin,
you'll get peaking.
And given the Inductive output impedance of OpAmps, any Cload (unless well dampeded) makes that opamp provide output peaking.