Because of just how hard you seem to be trying to attempt to deny how bad this warlock is.
If Mystic Arcana, as your post indicated, is actually all that then any sensible person would accept that it is unequivocal that the warlock took some utterly and truly savage nerfs in this version. They had mystic arcana and high level invocations.
Or to put things another way if WotC think that Mystic Arcana were what warlocks needed to keep up they should have made them into class features. Which they did in the 2014 warlock. But took away for this cheap knock off.
In other words your attempt to claim that Mystic Arcana give the D&Done warlock what it needs is a damning criticism of that warlock.
I find it very strange that you had the sheer nerve to call my comparisons shallow and claim I don't see the forest for the trees. Despite the fact that I'm the one who's been talking about how the whole package fits together and the one who's been providing numbers and analysis while your defences of this warlock appear to be all vibes-based and many of them are, like your latest, self-refuting.
Goodbye