Surely a discussion on UFOs as a folkloric phenomenon would be more useful / interesting / appropriate here than another slanging match on the ETH (Extra Terrestrial Hypothesis)? Of course there are no extra-terrestrials visiting Earth. Why? Because the experience & interpretation of UFOs is entirely subjective, rather like ghost & fairy-lore, albeit with a technological twist by way of added plausibility.

As with ghost & fairy-lore, there emerges a canonical conscensus by way of an objective framework on which to hang at least a measure of objective commonality. Thus does the folkloric nature of that commonality take on a life of its own, as can be seen with UFO-ETH community / culture. But make no mistake, it is the objective commonality that insists on the subjective experience (or at least its interpretation) and not the other way round.

I do not doubt individuals have experience of UFOs - likewise ghosts & fairies etc. if it comes to that; I know I certainly do, as do most other people I've talked to - but it is the interpretation of that experience that is the interesting thing.