You are technically correct. Many critters know as insects are their own group.

However in reality it has much more to do with human classification then actual nature. Same with what we call “fruit” so i al not sure what people want me to use to refer to the entire class of creepy crawlers.

Termites where for a while considered a different class but now there seen as a subclass of cockroaches and those are insects. Springtails where long considered insects but now they are their own class.

35mm without the legs is freaking huge. And as an arachnophobe you can’t tell me the legs don’t count towards its intimidation.