WOTC is literally changing that in the next new PHB.
So they found is "what we have now" doesn't work.
And even more Jeremy Crawford today stated that there were high popularity low satisfaction classes and low popularity high satisfaction classes.
They're tweaking a lot of things. There's always room for improvement. Like other posters have stated, if it weren't for the forums I wouldn't know anyone had an issue with the fighter. It's ranked as one of the best classes, people have fun playing it.
All I can go by is my experience and what I've seen over the past decade with a number of different groups. Fighters are not a drag on the group, even up to 20th level they still contribute. They just contribute in different ways than some of the other classes, which is a good thing.
Now if the mundane warrior is supposed to be able to specialize in 1-3 fighting styles and the mundane expert is supposed to be able to specialize in 4-8 skills, then we should just choose whether it is a supernatural or nonmagical process or both.
No, no we don't have to take your assumption of what they "need". I don't want my fighter to be overtly supernatural and doing obviously magical things. Unless of course they're an Arcane Archer, Eldritch Knight, Psi Warrior, Rune Knight or the fighter adjacent classes like paladins or unless they multi-class into a spell casting class or they ... well the list goes on.
If I want a fighter that does magic there are plenty of options. I also want the option of a fighter that doesn't do magic.