I mean, he could, but wouldn't he need Congress to confirm his appointments? They'd just do what they did while Obama was in office and block any motion for a vote, especially since the Democratic party doesn't hold a filibuster-proof, 60-member Senate majority. Although, Obama had that and still blew it, the price of believing one can still engage in good faith negotiations with bad faith actors, I'm afraid.
They're already declaring their intentions to not negotiate with Harris in good faith, should she win the election, and to block all Presidential appointments. Hopefully she will go ahead and do it anyway. SCOTUS does get the final say in what does and does not constitute an "Official Act", but they don't have any enforcement mechanism. All they can do is send a strongly-worded letter, asking her to stop, but they can't force her to stop.
Well, yeah. "House" no longer means "Place where people live". It's now defined as "long-term investment/passive income generator".