Like crop circles, flying saucers will die a death of banality as the "sightings" go nowhere and make no difference to anyone's daily life.
If "they" are out there they wil not rely on zooming around the upper atmosphere and bending wheat fields to let us know.
It did increase after WW2, see project sign etc., the 1940s were the beginning of everything relating to the end times, wars and rumors of war as Jesus said, the dead sea scrolls, Israel restored, computers, atomic bombs, traveling to and fro with knowledge increasing etc., “but the end is not yet” see Matthew 24:6
I believe an omnipotent and creative God could easily (and very likely did) fill up the universe with his creations, but what ever may be out there is not superior to us, we’re made in his image
However, I believe what we’ve been experiencing as ufo sightings throughout history is not physical but instead spiritual in nature and have to do with angelic and demonic warfare taking place and spilling over into the physical world and will likely increase as this age gets closer and closer to the end,
Also I suspect as we approach the 70 year mark from events in that time, that it may be prophetically significant,