My daughter spoke four languages at age 3. Not because she is gifted, but because she grew up in an immigrant environment. One language with me, another with my partner who speaks a different mother tongue than I do, and the two local languages where we live.
And this is utterly unremarkable where I live.
When we visit my family (who are all monolingual), they think she is a prodigy.
She’s not. She’s just a normal kid.
Learning by immersion is a completely different process from learning by being tutored, never mind learning by oneself from books.