Less than what? And how is it objective? They're not "less" than anything or anyone just because they can't do magic. Is Rayla "less" than Lujanne because she only uses the innate moonshadow elf powers?Humans without magic are objectively less. Why shouldn't they have it?
Humans should be able to use magic if they want to, but they shouldn't need it. We don't know why it was believed that they can't use primal magic until Callum managed to. Or why it's believed that elves can only use one primal arcanum despite Aaravos using more. But calling them "lesser beings" like Sol Regex does is wrong regardless of whether or not they're able to learn primal magic or dark magic.