The only problem is that there is no method to confirm anything a philosopher might say, as far as I know, which means we would have to trust them and they could be wrong all the time.
Ironically you can say the same thing about any religion.
...Especially the religion of atheism.
Philosophy is often trial and error, same as science.
Since religion is how you live, experience eliminates some of the trial and error of life in the future.
Philosophy is merely an outlook on life, nothing more. It can be shaped by anything, be it fact or fiction.