I checked the raw and yeah he's not saying spears are unsuited for combat, he's telling her to narrow it down to combat specifically.
「武器は何を使う?」
"What kind of weapon(s) does she use?"
「魚を獲るときには槍を使ったことがあるそうです」
"Apparently she's used a spear when catching fish"
「それは銛では?」
"Does she mean a...