The vast majority of people don't operate on reason and logic. Most people don't even understand basic logic. Most people operate on preconceived notions, and seek to verify their existing beliefs, not to find the truth.

This applies to the religious and atheist, scientist and layperson, conservative and liberal, alike.

Even in the educated, scientific world, it's common to dismiss philosophy, and only subscribe to skepticism, which is only one narrow worldview. That is, just because you can't prove something doesn't mean it isn't true; or in logical terms, absence of evidence isn't evidence of absence.

Would you disregard these doors and decide to build your own door?

I dunno, I've seen a lot of people build their own doors. They don't really look any better than the mainstream doors. Which leads me to believe building my own door wouldn't, either.

From the outside, each door looks the same

But they don't. Many of the doors are inscribed with fear, hatred, and violence. I tend to avoid those doors.

Each door in front of you claims to have the true meaning to life.

Always We Begin Again, a modern reinterpretation of the Benedictine Rule, starts with:

renounce the delusion that the meaning of life can be learned

In fact, for your questions, it seems like it might be right up your alley. It's a very small, short book, which mostly consists of advice for living. It reads a lot like a Buddhist text, in that way. I was first given it by someone whom I have an enormous spiritual respect for, who was in turn given it by a Benedictine nun. If you like, I'd be more than happy to send you a copy, if you have an address, or email for a Kindle copy.