I don't really see how that can stick. Even if the next president is Republican, he's not going to want to be limited like that in decorating his office. That's not even talking about how unpopular Trump probably is with a lot of Republican politicians right now, much less Democratic ones.

Even if he gets this through in the next few weeks, even if the current Congress is inclined to go along with it, as soon as Trump leaves office, how does it stay? Not like even a Republican Congress is going to care about retaining Trump's Oval Office decor.

I saw Nate Silver speculating—I don't know how seriously—that Trump might, at this point, just toss the GOP under the bus and cut a deal with the Democrats to get his triumphal arch and ballroom in exchange for giving them policies that they want. Silver's point was that Trump really cares about his legacy, and there's not much that the GOP can give him at this point (well, after January 3). But even in that scenario, which I dunno if I buy into, I can't imagine that future presidents would be handcuffed on their Oval Office decor. We've always let presidents recorate it.

EDIT: Oh, wait, I hadn't read the article. He's doing it via presidential authority alone. It does look like that's possible for a national monument. It does look like current precedent, though, is that a later president can just remove protection without going to Congress, so if that precedent stands, I think that it has basically zero functional impact; if a subsequent president wants to redecorate his office, he just removes protection and then redecorates it, and he'd be the one wanting to do so anyway.