I think this is pretty clearly just a humorous, fun exercise by frustrated Nets fans. I didn't hear when Simmons brought this particular obscure rule up, but I did listen to his "mock expansion draft" podcast where he and Russillo pretended they were GMs in the eventual Vegas and Seattle expansion drafts. They went through each team, deciding which players to protect and which players Vegas or Seattle would take (if it happened today, of course). It's just for entertainment, basically, especially for fans who like to play armchair GM.