Not worth an errata (are there even any feats in the SCAG? Oh, the Deep Gnome feat. Already worthless since the Monsters of the Multiverse release)
Just assume any feat that doesn't have a level is a level 4 feat. I mean, if you need official word from Wizards, they can literally just add that sentence into the PHB. There is no reason to reprint entire books just to list levels by feats.
Also, I want to note. None of your previous objections (the four I listed) included "they are giving levels to feats so they need to reprint every feat in the game". So, we are up to five objections and only two of them have any real merit it seems, one of which is a simple fix and the other which is a legitimate concern.