You make a fair point, but we aren't discussing hearsay; every aircraft accident has a detailed documented investigation. This investigation would involve many different professionals and need to gather evidence. If all of them were made to provide the same lies, this would be a bigger conspiracy than some would have us believe the Princess Diana affair is! I'm sure there would be an equal amount of Internet conspiracy theories, which Naomi would also be aware of, and which she obviously must have dismissed as cranks.So, you believe everything you hear on the news? Ask Dan Rather what he thinks about that.
On the other hand, at the very beginning of the 3rd Season we see the aircraft break-up in the air, and clearly already on fire, as it crashes. This fits with different parts on the craft landing in different areas of the Island. It does not fit with it crashing into the sea and lying at the bottom intact. I have also heard that commercial aeroplanes very rarely land at sea and deploy the slide chutes, that if they crash at sea they generally go straight down. I tried to get some figures about other crash examples, but can't find any, however accidents in the air due to the aeroplane itself, or even due to pilot error, are quite low. Most accidents are on take-off and landing.
The original theories that Sayid had planted a bomb would actually fit the facts much better, but we now know that was not the case.
Something about the crash itself is clearly at odds with a normal crash, so we will just have to wait and see an explanation.