I'm about a foot bigger than Dunsparce, Dunsparce is just a big Pokemon (if nearly 5 feet counts as big).
Onix, Lapras, Seviper, Kangaskhan, Tropius, Aerodactyl, Wailmer, Ekans, Dratini, Skarmory, Druddigon, and Bouffalant are all bigger than Dunsparce.
Hitmonlee, Scyther, Pinsir, Girafarig, and Heracross are of equal height.
So what's the problem here?
Hell Noctowl is 5' 03'', that's ONE big bird, for a fully evolved one.