One of the problems in creating a magic system is that it has to blow your mind. It has to feel magical and special. It has to give the element of wow and look what I found. Look what I can do with this.
Bingo!
And right there, ladies and gentlemen, there is the essence of D&D. Magic has to feel "magical and special". Which means it HAS to be better than non-magical, otherwise, it's not magical or special and doesn't give that element of wow and look what I found.
Imagine a D&D wizards needed to spend hours to cast a single spell. Or days, or weeks even. Where no magic item is better than a +1 sword. Nothing. Magical items are never more powerful than a +1 sword.
People would absolutely hate it. It wouldn't even be considered D&D. Heck, apparently allowing a 23rd level character to jump twice as far as normal is a bridge too far to keep it in the D&D family.

Sorry, bad pun.
All these examples do nothing but prove the point. We LOVE finding that ring of regeneration. We REMEMBER that Holy Avenger. Table goes nuts when the wizard drops that second fireball on the baddies, turning them all into crispy critters. How did you beat the gathering of giants in the Hall? Well, we dropped two fireballs on them and those 42 hp giants all went poof. On and on and on.
Magic being "magical and special" (if that's a more acceptable phrase than "Primacy of Magic" ) is the essence of D&D. It's the one strand the binds all editions together. Stray from that and people start claiming that it's not really D&D anymore. Doesn't matter whether I or
@Tony Vargas or
@lowkey13 all think that 4e is part of the D&D family. I know that we do. But, the broader perception, that unless Magic is "magical and special" it's not really D&D is very real and very easy to display.
Where
@lowkey13 is making a mistake is that he thinks that I'm attaching a value judgement to this. I'm not. I'm simply looking at the facts.