If you’re looking for iOS 14, I am not sure. I bought Apple refurbished iPad Pro 2020 3 weeks ago (for my father) and it has 15.1 pre installed. But old stock may still available.That would mean iOS 15/16 preinstalled so nope. I was originally planning on waiting but only so I could get a refurb 2021 discounted. Mini-LED isn't make or break for me.
In any case, there's nothing stopping me from buying a new Pro if I really wanted it. Besides, there's a Pro 9.7 and 6th gen in the household that have gotten quite laggy on iOS 15 and are begging for upgrades.
On the other thread, I shared that 15.3.1 is running very smooth on M1 11”. I may stop at this version, unless there is severe security issues / bugs that stopping me for my usage.