Peer-review is not a part of the scientific method. Period.
The peer-review system, as it exists in its current form, has only existed since the 1970s (maybe 1960s in some cases). It is a relatively modern academic gatekeeping process, it’s not an ancient pillar of science.
Issac Newton, Galileo, Charles Darwin, and even much of Einstein's work (specifically his four Annus Mirabilis papers in 1905) were published without “peer-review.”
Science advances with new evidence, replication, and falsifiability. “Peer-reviewers” typically do none of the above things when reading over a paper that is submitted to an academic journal. Reviewers are anonymous “experts” who often just stamp approval for any papers they happen to agree with and reject ones that challenge their own biases or research because they want to be right.
Just because something has been “peer-reviewed” does not necessarily mean it is accurate.
And just because something hasn't been subject to the academic circle jerk does not necessarily mean it is invalid.
Your peers agreeing with your ideas does not automatically make your ideas valid.
“Peer-review” approval not the arbiter of truth. It can be. Sure. But it can also be gatekeeping.