A permanent coil and moving magnet are used as a seismic geophone. The coil has low impedance like an 8 Ohm speaker.
The typical (high dielectric constant) ceramic capacitor is well-known to generate piezoelectric currents, also known as microphonic in relatively high impedance circuits. A 1nF capacitor is about 150kohm at 1kHz which is "relatively" high impedance.
PZ accelerometers are even more sensitive to vibration with the crystalline ceramic materials used.
A cheap electret microphone has a FET buffer rather than a charge amplifier so it basically detects sound as air pressure velocity, not acceleration. With backside partial cancellation. But the derivative of that signal might be an indicator of acceleration, but rather crude and non-flat frequency response.
Comparing accelerometers is like comparing mics.
An electret mic needs an internal FET to buffer the audio with a 10k to 33k load resistor to provide bias and gain from the modulated charge current from the PZ element.
A magnetic mic is a relatively low impedance using a moving coil and permanent magnet. The PZ electric mic is similar with a stored charge that is modulated by vibration but higher impedance due to the fact the ceramic is an insulator and the moving coil is a conductor.