The LOTRO forums are ablaze with discussions about upcoming changes to keys and lootboxes at all levels in the game. IMO, the devs have done a poor job of explaining what will happen, and it seems clear they are still making changes as one forum poster or another raises an issue they didn't think about.
You may have heard me say something like "Surely they won't ..." in trying to make sense of what I heard about these changes. However, it appears that they are, in fact, planning to alter the role keys and lootboxes play in the game including, for example, anniversary gifts of keys, quest and deed rewards of keys, availability of cosmetics, and more. Previous statements they made and preliminary conclusions I might have reached are no longer valid.
So far, there is no coherent authoritative description of what will happen. We have been promised a "heads up" post before launch, but what will become of any bound or unbound Sturdy Steel Keys or Black Steel Keys or lootboxes of any level is uncertain at this point. One thing that has been repeated is that new keys will only come from the LOTRO store, so if you have nothing better to do, you may want to do some dailies to get a few more, but who knows if it will be worth the effort.
This is the best summary I've seen, pieced together from different posts, but of course it is subject to further changes and interpretation:
https://lotro-wiki.com/index.php/Commentary:_End_Game_Loot,_Lootboxes,_Update_23,_and_Beyond
Fasten your seatbelts. It’s going to be a bumpy night.