Unfortunately, the results of the peer review process are erratic. Reviewing a paper takes a lot of time, so many scientists will just rubber stamp any papers that don't appear to be from crackpots. Even carefully reviewed papers will often contain subtle errors that invalidate the entire analysis.
The true peer review process, in my opinion, occurs at the global level. Exciting results will be debated, reproduced, and reused by astronomers around the world. Anything that can survive this kind of scrutiny becomes accepted in the mainstream and is used for subsequent research.
Nothing is off limits, though. Famous and seemingly dogmatic results are constantly being revisited as new data arrives or as we gain theoretical insight. If you're taking anything on faith (or philosophical prejudice), then you're not doing science.