This is not a duplicate of earlier questions asking whether or why the comma splice is an error, because I am asking about the debate itself: unlike many another grammar rule that is widely accepted by all parties, why are so many people on opposite sides when it comes to the comma splice?

I see comma splices every day in very well written members' comments on multiple Stack Exchange sites and also in so many articles on the World Wide Web. My mind keeps identifying the comma splice and suggests the semicolon as a possible alternative. With such widespread use the comma splice seems to have gained descriptive legitimacy. I sometimes use comma splice myself and only recently learned that some grammarians consider it an 'error.'

Looking back over the previous questions about comma splice I came across this unanswered Q:

Why is the comma splice an error?

And I was surprised to see I had already posted this comment:

It seems that comma splice is now considered legitimate. Many members here use it regularly in comments and some even in answers; and at least one senior member (I forget who because it was 2 months back when I was new here) advised me outright that comma splice is preferable to semicolon in modern English writing. – English Student Jul 15 at 1:43

To which another member had responded,

incorrect usage by senior members does not justify it. It is still incorrect usage, although comment sections are hardly the best example of a context where proper use plays an important role. In formal writing, the comma splice ought to be avoided. – Octopus Jul 15 at 3:09

Of course I am no grammarian myself, and this is not a duplicate of that question but a query as to WHY there is still grammatical debate rather than consensus over the comma splice.

Specifically, what grammatical reasons prevent users and grammarians from reaching a consensus on the issue?

I welcome adequate references to ensure that your answers are not read by others as 'primarily opinion based.'