Does the RODE PodMic need a booster into the Focusrite Scarlett 4i4 4th Gen?
Yes. At speaking level the PodMic needs about 57 dB, and the Scarlett 4i4 4th Gen publishes 69, so 12 dB of gain is spare. Those are the published figures.
The RODE PodMic has enough preamp on the Focusrite Scarlett 4i4 4th Gen for a normal speaking voice. You do not have to add a box in front of it.
RODE rates the PodMic at -57.0 dBV/Pa, the voltage from a loud 94 dB tone at the grille. A speaking voice is closer to 85 dB, so the preamp still has to find about 57 dB to land near −9 dBV. That −9 dBV figure is just a tracking level: high enough to use, with space before the converter clips.
Set the knob for the voice you actually record and leave a little travel for plosives, instead of pinning it because the spec sheet has a higher number. A booster on a chain that already has about 12 dB spare only adds a box. Most of those boxes also use the phantom power themselves, which will silence a condenser.