The entire purpose of the Stepien Rule is to prevent teams from trading too many 1sts for their own benefit. This scenario has no bearing on The Stepien Rule whatsoever. It still applied to the Nets when they traded for Garnett and Pierce (where they traded three unprotected firsts but had to trade picks from every other year, in addition to agreeing to pick swaps in the years they weren’t outright trading their picks), for example.
I don’t know if it’s possible to go back and negotiate new pick protections on a pick already conveyed, but that could be a way to make our 1st owed to the Grizzlies convey earlier and making a 1st tradable earlier than 2024 if that is a thing that is allowed. Hypothetically.
Most importantly, that is an absurd idea. I’m rolling with JFC over Iggy without blinking.