Seems that way and I wouldn't be putting any money on that happening in the near future.
Not just aliens and UFOs, but the decline in reported Paranormal stories and experiences, ghosts, strange occurances and so on also seems to be on the decline... Here's an interesting British article, seems to have been written early this year:
NO SPOOKS ON THE AIRWAVES – THE DECLINE AND FALL OF GHOSTS AS A TOPIC FOR BBC RADIO
Long ago talks and discussions of ghosts and ghost hunting were a feature of BBC radio, with the subject being covered seriously. Sadly, the treatment of the subject has now declined down to a purely humorous level, if ever mentioned at all.
THE DECLINE AND FALL OF GHOSTS ON THE RADIO | Europaranormal