We all know that giant spiders are a very common enemy in the fantasy genre, both tabletop and digital, but is this justified? How would a spiders act to humans if they were the size of a dog? And how would they act if they were the size of an elephant? Would they really be this extremely dangerous infestation of human eating abominations, or is the threat much more limited than is often depicted?

Pic only tangentially related, no need to thank me arachnophobes.