"that being said" - why?

Welcome to the forum!

The phrase "that being said" does have its place, as when the following assertion follows from, or requires, the preceding. It's synonymous with "thus" or "ergo" or "therefore" or "consequently."

But I do agree it's overused these days, and is more often used as "filler," when the speaker needs time to select the right words.

I think people say it (sometimes) to excuse what they have just said because  what they have just said  may contain some  opinionated snark that might/could raise an eyebrow.    The phrase can reek of some kind of odd self-importance.   The public domain nature of  this tiresome vocabulary filler, and possible verbal tic, that has become epidemic raises the puke reflex in me, too. That being said and  at the end of the day, the bottom line is you can take all of the low hanging fruit and ultimately, we can  move forward in our upaced and dynamic work environments.

Amen. As shown by our recent track record.

I'm with everyone here about overuse, and of course other phrases can be overused the same way.   I had a boss who could be counted on to say "in terms of" at least once every other sentence:   "What progress have we made in terms of project A?"   "Roxanne called; they're unhappy in terms of the the plan we laid out for them."   As you say, it became clear that in his case it was a phrase that gave him time to think about whatever he was going to say next.

Heimhenge, I don't usually hear "that being said" to indicate that what follows from what preceded, but rather the reverse.   "I usually prefer reason over emotion; that being said, in this case I think it's better to..."   "The population is well within the limit; that being said, perhaps we should wait a bit longer."   It seems to me that "that being said..." means something more like "nevertheless" or "notwithstanding".