This is an issue of semantics that can become huge. You see it to a lesser extent with issues like 'is a hippogriff an 'animal?' What about a genius talking snake?' People loaded up with Charm Animal and Speak with Animal and Animal Husbandry need to know!
|Is a 360 spin attack magic? What about 720?|
|Giant defies square-cube law- magic or not?|
|What about your ENTIRE setting that the gods forged with their magic powers out of primeval chaos?|
|Is wuv, tru wuv, magic?|
Now, you can solve this by making a 10 page list of everything that is and isn't 'magic,' maybe establish success rolls power hierarchies to keep things 'balanced' in terms of mathematical combat exercises
OR you can agree that I am the brainiest brain to ever brain and that for 99% of fantasy settings, everything is functionally magic and you should either revamp or do away with stuff like 'dispel magic.'
'Counterspell'- Lord Sicknasty tries to cast his patented 'Sicknasty Scorcher' but Gandolfo the Original Character is having none of it and casts 'Counterspell' and so the status quo of 'whoever has the brawniest sword-dude wins' is upheld. In more freeform systems this can manifest in classic wizard-duel fashion of counters countering counters- Sicknasty Scorcher is countered by Gandolfo's Invocation of Ice rather than a generic 'counterspell' that sorta thing. But the key here is that you are countering specific things, not ''magic'' itself so it is easier to have lore-friendly magic busting.
'Wizardly Knowledge'- Rather than have the wizard be the solution, the wizard can at least always know the solution. If you're leaning more storygame, the wizard can actually just make up what has to be done to overcome the magical obstacle, or they can relate information from the GM to the party.
'Pain In The Ass Ritual Dispel' If you need to find 6 other spellcasters and then dance in a ring on the full moon as you ritually burn 2000GP worth of gold-embossed prayer scrips, it becomes serious business again, and a question of time and resource management, which is classic goodstuff for dungeon delvy campaigns.
"Reduce Duration" Dispel magic does have a place in ending buffs and debuffs so a spell that cuts remaining duration of a spell down by a round per level or so fulfills that niche without becoming a one-size fits all option. Alternate modes like 'Diminish Area' or 'Weaken Effect' or 'temporary suppression' could also be viable 'dispel' choices that allow the wizard to protect people from magical effects.
'Into the bin' The Greek Gods either couldn't or wouldn't undo the various curses they slapped on mortals. With this option, there's no takebacks on magic, which I think is appropriate. Actions have consequences, being a wizard means knowing when it is wise to use magic and when its better to just stroke your beard mysteriously, that sorta thing. Magic run amok stays amok.
"Dispel Magic" Also known as "Double Forbidden Void Unraveling" because guess what, the world is magic, souls are magic, feelings are magic, and this spell takes something of this wondrous world of magic and straight up unmakes it, leaving an unspeakable gulf of nothing behind. Because THAT'S the sort of blunt instrument for brute forcing problems you give the players, just to see how much trouble they get themselves into with it.
"Divert Magic" What if you could get rid of curses by moving them onto willing subjects? Get rid of that wall of fire around Brunhild by setting it free as a roaming fire-monster? As you can probably tell, I'm fond of solving conflict in 'messy' ways that leave more loose ends then they resolve, because you can take those loose ends and weave a long campaign out of them.
"Dispel Fantasy" Save or lose genre. The dragon becomes a poorly-lit crocodile, the treasure hoard becomes a shipment of cloves in an abandoned wagon, and the party is declared outlaws upon attempting to sell stolen cloves without a spice permit, and they die of dysentery after drinking water without boiling it.