Maximum speed v=A*ω (amplitude times the circumferential frequency of vibration).

Indeed, if a is constant, the greater ω is, the greater the maximum speed is.

But when forced to vibrate, a changes with ω. When ω is very close to ω0, the amplitude will become huge. Therefore, on the whole, v is large when vibrating.

Note: There is a formula for college physics:

A 1 is the steady-state amplitude, f0 is the driving force, ω is the driving force frequency, ω0 is the * * * vibration frequency, and β is the damping. It can be seen that when the damping is small, if ω is very close to ω0, the amplitude will be larger.