BJT Capacitance at RF limmitations
The gain.BW product for this component is min. 650 MHz. Let's use 900 MHz. So at 90 MHz, you can only expect a gain of 10x. Some of the reasons for limited Gain.BW are B-C and B-E capacitance, as well as base resistance. Your 500 ohm emitter R will then look like 10x = 5k when reflected to the base. When driven with a 20 kohm source, you will therefore only have a gain of ~ 5k/(20k+5k) = 0.2.

Now, your 3 Vp-p @ 90 MHz requires a slew rate of 3V*90M*2 = 540 V/us. With 10 mA bias current, you can calculate the max. capacitance allowed at the emitter to support this slew rate -- from I=C.dV/dt, you get C = 10m/(540V/us) = 19 pF. This is larger than the B-E capacitance, so you should be OK there.

Generally RF circuits don't use such (relatively) high impedances as you have (20k) -- then the relative effect of the parasitic capacitances is smaller.

You could use a somewhat higher emitter R -- to get slightly more gain; then add a 2nd stage (which would now be driven from a lower impedance (=re of the BJT, ~ 2.6 ohm @ 20 mA).