"It's like saying an engaged couple is divorced because they're not currently married."

The two are nothing alike because banned may have a different connotation for you but its use is proper by the denotation of the word. Your example is not correct by the common connotation or denotation of the word.

For those that down voted my answer I would like to point out that I wasn't the one to originally use the word "banned" to describe the status of the vaccine nor would I normally do so. I was attempting to explain the thinking behind someone else using it.

That is not the proper denotation of the word. The FDA has not placed any ban on the AstraZeneca vaccine. The FDA has not yet approved the vaccine, and there are various limitations on what can be done with a medicine prior to approval (note these limitations are on manufacture, importation, and marketing, not on taking the drug, you can easily and legally be prescribed and buy unapproved drugs), and approving the vaccine could be thought of as analogous in several ways to lifting a ban, but it is incorrect to say that there is a ban for the FDA to lift. The FDA can ban drugs, and there are many that it has, but AstraZeneca's vaccine is not one of them.

Likewise, an engaged couple is just as un-married as a divorced one, and there might be various analogues between a divorced couple getting remarried and an engaged couple being married for the first time, but it is still incorrect to say an engaged couple that has never been married should get remarried.

The definition of ban is "officially or legally prohibit". The use of the AstraZeneca vaccine meets that definition until action is taken by the FDA.

The definition of divorced is not un-married. It is "no longer married because the marriage has been legally dissolved". Unless the engaged couple was previously married to each other they don't meet that definition.

I think you're at risk of wanting to be more right, than advance the discourse. What can we say, who believe you used ban in a technically correct but misread and misreceived manner?

Try not doing this. Try to consider why another term might be better.

AstraZeneca's vaccine is not officially or legally prohibited by the FDA. It's impractical but perfectly legal to acquire and use.

Pending approval != banned to exactly the same degree that pending marriage != dissolved marriage.