"You guys are reading too much into this... There's no way that any reasonable person would consider that an official act and this hypothetical president would surely be swiftly impeached and convicted. You're worrying over nothing."
That act won't really hold up. That's not really an action. It's taking away something ephemeral. Rights are not in the physical world.
Now, jailing Donald for crimes. That's doing something physical. And the Supreme Court could rule against him, and Biden could say, "Make me." And Don would continue to be jailed illegally. And the Supreme Court would have no say over the impotence of their own creation. And we'd have an impeachment hearing that won't go anywhere.