IME DMs that ban these kinds of spells have problems getting players to the table. That said even when these spells are available, they are not universally taken.
And yet my point still stands.
What is banned from the Fighter Class? Not from feats, but from the fighter base class. Have you ever even heard of someone starting a thread with "My fighter reached level [X] and now has [Y] and they just ruined this encounter, how do I prevent this?" Because we hear it constantly for spellcasters.
That is not the only thing those classes are good at. The reason fighters in particular are only good at hitting single target enemies is because players CHOOSE to make their PCs only good at that.
Most of the people who play fighters that are only good at combart also play fighters with a 14+ in Constitution (usually a 16+). They dump every useful ability in the game, purposely build their character to be good at only single target combat and then complain that they are only good at single target combat. I purposely positioned my ability scores so my fighter is a dumb, irritating clutz and now I can't figure out why no one likes him, why he can't solve and puzzels and he trips over his own shoelaces!
If you want to be good at other things, play a Fighter with a 10 Constitution and a 16 in Wisdom or Charisma and it is a whole different ballgame and that character is still good at melee.
So, make the character on the front line more likely to die, and focus on... what? Wisdom and Charisma are only useful if you have... skills.
I mean, sure, yeah, you can build a fighter who has less hp and instead has a high charisma, which allows them to actually succeed at persuasion rolls... But they can't read minds. They can't change their appearance with a single action. They can't charm. They can't suggest courses of action. They can't dominate people into doing their bidding.... But bards can do all that. And a bard with a high charisma is also good at the skills, better with expertise, AND has magic to supplement that.
OR Wisdom, by which you are likely focusing on perception. But... while perception is useful, what can the fighter do that is equal to detect good and evil? Detect Poison? Detect Magic? See Invisibility? True Seeing?
Most people aren't stupid when they build their characters. They give front-liners high Con because they get hit the most, and they don't want their characters dying. But even if a fighter puts a high score into wisdom or charisma... they are still limited. They are limited to the skills and what the DM allows. They can't break out of that.
What if, by level 10 or so, a martial character with Investigation could roll and on a success, they discover enough clues to actually get to "see" what happened in a room? The DM would describe to them, for example, that two men slipped in through the window, startled Mr Darcy, who ran for his sword, but he was hit by a thrown dagger with an ornate handle. The two men dragged him back to his chair, where the second used magic to seal the wound, and make it appear as though he died of natural causes.
This is something that absolutely happens in fiction, with skilled investigator characters, and if the player knew that, they might be far more interested in putting a higher Int on their character, and building towards that ability.
OR, if they want to play the jock fighter, maybe give their athletics a way to destroy scenery more easily, or an ability to ignore environmental damage and effects through sheer toughness (Oden standing for an hour in a pot of boiling oil to save his men from execution)
There are things that would allow us to compete or exceed spells, things we lack, and can't build towards.
Why shouldn't it be? Are you honestly going to say that asking the victim who killed her should be less effective at finding the murderer than looking around the crime scene for clues? And keep in mind the decision to have Speak with Dead available is a decision with real, tangible cost.
There is always the option of just banning magic outright, and the game is still very playable like that.
Should be less effective? No. But at that point, are you really going to say that catching someone on fire is should be less effective than shooting them with an arrow? Taking Firebolt is a decision that has a real, tangible cost too.
So what is the BENEFIT of not taking magic? Armor and HP? Clerics and Druids are going to be running around in heavy armor with d8 HD, Bards have d8 HD and light armor, same as rogues. The highest AC builds are usually magic using characters, like Bladesingers, forge clerics, and Eldritch Knights (which I know is a fighter subclass, but they are the fighter subclass that USES MAGIC, so what is the benefit of forgoing that?)
Damage? I'll admit, Fighters and Rogues are not slouches when it comes to single target damage, but generally, full caster optimizers SCOFF at the idea of building blasters. It is the LEAST effective thing you can do, in their mind. And trust me, I've seen first hand it doesn't matter how much damage you can do if the enemy can't touch you for 10 turns of combat.
So, what I want, is for these classes to have out of combat options, that can at least compete with spells. Sure, Speak with Dead is a great spell for solving murder mysteries. It is also not even a blip on the design space of full casters. Remove it from the game, and most casters won't notice a significant drop in strength. So it shouldn't be hard to ADD competitive options to the skills of martials. Casters will still likely get them first, and maybe even stronger, but it will at least give the martials something to do, built into the system.
If you are talking about spells, this is not actually true until 11th level and every class can do impossible things by that level.
What does the 11th level fighter do that is impossible? Make more attacks? Re-roll a save? That's it. And those aren't impossible things. Those aren't even notable things, in terms of plot impact. No challenge or encounter is going to be circumvented or even significantly impacted by that.
Meanwhile, most casters have a dozen spell options by level 8, and by that point they have access to 4th level spells, which are doozies.