It is a reasonable question. I tend to write like I talk, which the Chicago manual of style frowns upon. It isn't a particularly 'creeping' pattern, it is quite common amongst people with whom I have regular informal conversations.
That said[1], I probably feel the same way about the use of 'because' in informal speech. Which was recently upgraded to include the form "because <noun>." I don't find that a particularly compelling upgrade.
There was a recent album release called "Because the internet". Absolutely horrific :-)
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I think what gets me about leading with "So" (more so in spoken converstaion) is that it makes the speaker sound like they're constantly, and consciously, having to reframe things in a form that the poor dummy they're speaking to will understand.
Politicians do it a lot when answering questions.
I also recognise that it's more innocently used when telling a story.
I can see that aspect of it, I typically use it as an equivalent to "In my experience ..." or to convey a result that is derived empirically rather than reasoned do by first principles. I consider such things more 'as a personal preference' rather than having any sort of definitive reasoning behind them.
