I get what you're saying, so, let's ignore that. Let's ignore the comparisons between editions and how this or that edition does this or that. IOW, let's cut out the cruft and look at what's actually the point here.
Let's lay it out:
P1 Only one edition of D&D is routinely described by fans as being "not really D&D". Typically it isn't even a knock on the game really. It's often phrased, "It's a good game, it's just not D&D to me." Fair enough. That's the perception.
P2. 4e shares a great deal of mechanics and flavor with other editions. Someone coming out of 3e having been using things like Book of 9 Swords and Tome of Magic probably didn't see a huge shift in mechanics. And, moving from 4e to 5e, there are a number of elements shared. So, if the element is shared, then it's not essential to D&D since 4e is the "not D&D" edition. Lots of games share elements with D&D but are not considered D&D. No one calls Rolemaster D&D, despite Rolemaster and 3e sharing a great number of mechanics.
P3. 4e is the only edition to achieve parity between casters and non-casters. The parity isn't perfect, but, it's far closer than in any other edition.
P4. We have yet to see other elements that appear in 4e that don't appear in other editions to explain why 4e is set aside as "not D&D".
Conclusion: It is the primacy of magic in every edition of D&D that is essential to the D&D experience. Remove the primacy of magic, make magic equal to or weaker than mundane, and it is "boring" and "not D&D".
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Now, that all being said, none of that is a judgement of any of the games. Nor is it a judgement of those who play the games. Liking magic to be magical is not a bad thing. Liking mundane to remain in the realm of real worldish physics is not a bad thing. There's nothing wrong with that. Obviously. since we have about 40 years of D&D doing exactly that and people liking it. Remove that element - making magic equal to or weaker than the mundane - and you get an experience that people label as "not D&D".
Is that a fair summation?