Frankly, blind fighting sucks. In every edition (except those where it doesn't exist). It gives you a slight edge if your opponent is also blinded, but that's about it. It hardly meets a criteria sufficient to playing a conceptual blind swordsman.
This drives at my point. The D&D design for martial characters has generally to be to "err on the side of reality", resulting in fundamentally mundane characters. Meaning that martials generally can't even accomplish what accomplished people from the real world can achieve, much less their mythic counterparts.
If having the fighter wear a headband of the third eye allows the mythic blind swordsman to actually be designed "erring on the side of awesome/myth" while still preserving the sense of verisimilitude of the mundane martial crowd, I'd be all for it. Because it's the type of fluff I can easily ignore (obviously, so long as it is designed with the intent to be unobtrusive, such as these items not requiring attunement).
It isn't even erring on the side of actual reality though, where things like Legolas-style archery are actually within the bounds of human ability. It's erring on the side of "what a typical North American moderately-affluent nerd
thinks reality is." Fighters aren't even designed to be as capable as real-world Olympic athletes, let alone awesome characters out of fantasy,
regardless of level.
As to spells, I would say that the fault lies in design far earlier than that of 5e. As early as 2e, casters were allowed to choose their spells (even though it required a check to do so successfully). By 3e, I believe the check to learn new spells was only required for spells found in acquired spell books, not on level up. However, this isn't a trend that's likely to be reversed anytime soon. (The magic loving contingent would have a conniption if WotC tried.) So, IMO, the best open direction to take the design would be to make some magic items martial class features.
Well, as noted in my previous post, some of the antipathy here is completely justifiable. No one wants to have to jump through 17 annoying hoops to get to do The Cool Thing. The problem is, tradition has forced the power level of magic to remain extremely high or even to push it higher, while having constant pressure to remove the annoying, tedious, or frustrating mechanics that get in the way of using magic.
It's pretty reasonable to ask, "Why should I be the only person in the party who can fail a roll and, as a result, simply be
unable to use my class abilities?" The problem is, the answer
should be, "Because your class abilities were designed to be too powerful to be easily-accessed," but no one has the gonad gumption to actually
say that anymore, because that would be admitting stuff that pro-spellcasting partisans have been denying for decades. So the answer often
has been, "Huh, I guess there really isn't much reason for that, is there? Let's get rid of that dumb annoyance then!"
Spellcasters can no longer have their cake and eat it too. But taking their cake away is verboten, they'll howl bloody murder until they get it back
and an apology for having the audacity to take it away in the first place. The second option was to give non-spellcasters nice things. That had most of the same folks howling bloody murder again, claiming everyone had been turned into casters and a whole bunch of other complaints, so evidently that option is verboten as well. The only remaining option, then, is to spread around the love.
Which is why I said that our current state of affairs has, perfectly naturally, arisen from the old one. "Spellcasting is
technically optional but
practically necessary" has, by degrees, morphed into, "spellcasting is
technically avoidable but
practically everywhere." Because that's the only solution to the "spellcasting is too stronk" problem that won't make the pro-spellcasting partisans cry havoc and let slip the dogs of (flame)war.