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We can make an MMIC with discrete parts.
https://en.wikipedia.org/wiki/Monolithic_microwave_integrated_circuit?wprov=sfla1
As the typical Ft of a transistor like this is around 300 MHz, so assuming it is projected for a gain of 10 (20 dB), the maximum frequency will be at 30 MHz, above that the gain will decline. Using higher Ft transistors it is possible to extend the frequency range of use.
N.B as Hurz points out this is ok for HF, but using common general purpose low/ medium current transistors (2n2222, bc547 etc) we cannot amplify VHF or UHF.
The other thing, which is not easy to demonstrate on EC, is that around 17 MHz, for some reason we see a dip in gain, which recovers at higher frequencies. I have tested this with a number of general purpose transistors, and the results are always the same.
So, if we use RF low power BJTs with an ft of say 1000 MHz, this dip disappears.
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