The TO-251 (IPAK) through-hole package with short leads is a space-saver on single-layer boards — the tab is the drain, so the copper pad area under it sets the thermal resistance to ambient.
Parametric depth — gate charge and switching edge
Gate charge totals 15 nC at 10 V, which keeps the drive current low — a 100 kHz hard-switched flyback needs only about 1.5 mA average from the controller's driver. Input capacitance is 280 pF at 25 V drain-source, so the switching node rise time is dominated by the gate drive impedance rather than the miller plateau.