BJT high frequency analysis
From what I remember, the Cbe depends on the emitter current.

Higher current causes lower reac (1/gm); at 1mA, its 26 ohms. at 2mA its 13 ohms
2mA is 4 volts / 2Kohm (ignoring the emitter bypass cap).

Thus your circuit has an incremental emitter-base small-signal resistance of about 13 ohms.

If the 2N2222 has 160MHz Ftau, the emitter-base needs 1nanosecond time-constant,
or 1,000 picoSeconds TAU.

Given 1,000 pS TAU, and R of 13 ohms, the needed capacitance is 80 pisoFards.

However the large emitter bypass capacitor may influence this.