I have watched many interviews and talk shows in English and in many of them, when the host is saying goodbye, they say
"I've been Xxxx Xxxxxx and this is The Talk Show X!"
Why do they say "I've been…" when they can perfectly say "I am…"? Is there a rule for this or is this just popular language?
An example of what I'm trying to say is this video by Tom Scott (I've copied the link on the time he is saying goodbye because the video is too long): https://youtu.be/3kgI-TZXCa8?t=920
Best Answer
It began as a particular host's catch phrase some decades ago, and has gradually crept into more general use.
While originally used to make the host's sign-off more memorable (and therefore make the host more memorable), it was a play on the fact that the person's role as the host of the programme you had just been watching was now at an end. Essentially, a short-form of:
"I, Johnny Bloggs, have been your host (and now my role as host is over for now)."
which elides to
"I have been your host, Johnny Bloggs"
which elides to
"I've been Johnny Bloggs"