As I mentioned in another thread, it's literally like the writers of his solo show forgot Frost Giants also possess superhuman physical stats. Which would have been easier to ignore if they actually had him consistently use his magic to its full potential, but he doesn't do that either.
Contrast this to What If episode 3 where
Spoiler:
a version of Loki casually stomps Hank Pym Ant-Man while laughing at him. Meanwhile, Variant Loki can barely handle some fodder TVA agents...