While what you are saying is not wrong, it is only part of the story. You are assuming some sort of intention, however opaque, on the part of the speaker, when some speakers actually use these interjections and hesitations as a way to stall for time, apparently because they don't really know what they're going to say next. It particularly annoys me to hear this in podcasts or pre-recorded radio shows, and I have been known to write to the producer(s) to ask them to work with the (sometimes nervous or inexperienced) broadcasters to overcome their distracting verbal tics and get to their point, or if that is not possible, to excise these "fillers" from the recording before it airs. (Somewhat to my surprise, I have actually noticed improvements after sending these messages!)
So, in the past twenty years or so it became a thing to start a conversation or a fairly formal speech with “So,” Oxford comma or no.
And another thing (terribly OT) even Obama would repeat “is” as in “the thing is, is...” didn’t he?
While what you are saying is not wrong, it is only part of the story. You are assuming some sort of intention, however opaque, on the part of the speaker, when some speakers actually use these interjections and hesitations as a way to stall for time, apparently because they don't really know what they're going to say next. It particularly annoys me to hear this in podcasts or pre-recorded radio shows, and I have been known to write to the producer(s) to ask them to work with the (sometimes nervous or inexperienced) broadcasters to overcome their distracting verbal tics and get to their point, or if that is not possible, to excise these "fillers" from the recording before it airs. (Somewhat to my surprise, I have actually noticed improvements after sending these messages!)