Then in your model of the world, how would one not take a political stance?

If everyone takes a political stance in your model by definition no matter what their intents or actions are then it's a rather useless definition.

A segment of social media company staff also don't like that reality and want their social to censor the political parties / discussions they don't like and thus they toe the line and give unsatisfying non-answers at all hands and to the media.

Publishers are liable for everything posted on their websites. Platforms are not - as long as they make good faith efforts to take down or prevent posting of illegal content.

Both are allowed to engage in moderation, curation or "censorship". Engaging in such does not make a website a publisher.

Not really, no. That is not usually what people mean, when they say "take a political stance".

We can extend this to other examples. Do you think that a grocery store should ban people from their stores, if the individual is wearing a pro Trump, or pro Biden Tshirt?

I think it would be pretty silly to condemn a grocery store, for refusing to ban people from their stores, if they were wearing a "Vote for Biden/Trump" shirt.

Most people would find it absolutely and completely ridiculous to ban people from stores for doing that.

That's simply not true. One can verify the truth or falsehood of your statement by applying the knife of logic. Draw your statement to its logical conclusion in order to determine if it results in absurdity.

Let's do that.

A person who has had their brain surgically removed will (quite probably) never mention politics or attempt to control other's communications about politics. According to your statement, that person's actions are political. Sorry, but that's absurd.