Depends, older versions of UE4 (released around the same time-frame FF7R development may have migrated to UE4) did have LOD bugs like
this one which resulted in improper automatic LOD when using Build Scale. It looks rather similar to what could be happening with that apartment door and other examples which entirely fail to load a lower LOD. Either way though, even bugs such as that could be workaround when developers are aware of them, but I wouldn't really consider UE4's automatic LOD system to be flawless when it comes to visual fidelity without any additional effort by artists. It's part of what makes the tech in the new UE5 demo so interesting.
So, these posts are from 2014; there is no way that Square-Enix locked engine anytime before 2017 (I would guess a custom build of 4.21, if I had to). There are key improvements and important console SDK updates that are crucial to releasing any modern game.
In addition, what you posted isn't really a *bug* in the traditional sense, it's simply Unreal reading texel size from the original vertex data rather than looking at in-engine import scaling. Maybe it works either way nowadays, I'm not sure, but it would be very simple for a team to be like "hey we need to make sure everything is scaled properly in our modeling software", which they should frankly be doing anyway.
Unreal, like any engine, has bugs that pop up from time to time. You fix them or find workarounds or wait for the new version. Nothing should be a "surprise" that late in the game to any even remotely competent team.
That said, Square Enix made decisions to do what they did with the current technology available. I don't doubt they could have managed texture memory and pop-in better in certain areas, but I also understand they were under significant release pressure.