Shouldn't internal input resistance of a transistor be almost zero?
So, in terms of h-parameters, shouldn't \$h_{i}\$ be almost zero


Consider that the input to a BJT (in a common emitter configuration) is basically just driving a forward biased diode. Here's what a 1N4148 looks like just as an example. BJTs will be a little different in terms of collector voltage influences but well-within the same ball-park: -



So if you looked at the slope of the graph you could calculate dynamic input resistance versus forward voltage. At 0.8 volts the forward current is approximately 10 mA. At maybe 0.75 volts in, the current is about 8 mA. This means the dynamic input impedance is (0.8 - 0.75)/0.002 = 25 ohms.

At about 0.6 volts, the forward current is about 1 mA and if the voltage reduced to 0.55 volts, the current would be about 0.8 mA. Thus the dynamic resistance is now about 250 ohms.