You’re close, but the calculation is a bit misunderstood. The 32 dBm refers to the radio’s transmit power, while the 10 dBi is the antenna gain. These values don’t mean the device is transmitting 42 dBm of actual power. Instead, they combine to give the EIRP (Effective Isotropic Radiated Power).

So:
32 dBm (radio power) + 10 dBi (antenna gain) ≈ 42 dBm EIRP.

This doesn’t mean the device outputs 15.8 W of real transmitter power—the antenna simply focuses the signal, increasing the effective radiated power in one direction.