As the reader we have a relatively omniscient perspective, enhanced by the fact that at this point many of us have read the books and/or seen the movies multiple times and are quite familiar with not only the motivations and abilities but even possibly the extended history of the characters (including Sauron, Elrond, and Gandalf).
That is decidedly not the case for many of the attendees of the Council of Elrond. Even some of the elves present, and the (at the time of this writing) most upvoted answer on that question you linked makes explicit mention of this. Elrond is a famous loremaster who was present at many epochal moments in the history of Middle Earth and Gandalf even discounting his divine nature has walked the Earth for "300 lives of men" and delved deeply into the recordings of the past. All of the rich detail they know about the ring and the slim chance they have does not seem to be common knowledge, and as that answer points out even their knowledge of the military situation was incomplete. The point of the Council seems to be mostly to share that knowledge, convince everybody else, and get, in the parlance of our world, "buy-in" from those present.
Some present seemingly thought that if they hide it well enough, then they might (in their own minds) be able to stall Sauron for years. Maybe even thousands of years. Maybe forever. The full extent of the might of Mordor was not widely known, even if Gondor was slowly being whittled down (which was itself not widely known, Boromir has to plead his case). The information we know from Denethor's palantir is not available to them. It's obvious to us that without the destruction of the ring the cause is hopeless, just like it was obvious to Elrond and Gandalf, and perhaps Aragorn who was arguably the most widely-travelled person there (even if their knowledge was limited in scope!).
The thing the wise don't know heading in to the council is how they're going to get it to the Cracks of Doom. A question that Frodo of all people steps up to answer, and thus begins the tale.
TL;DR they debated it to convince those who didn't already know better what the proper course of action should be.