Im thinking more along these lines:
In one corner we have a level 25 fighter
In the other corner we have a level 18 fighter level 7 wiz or dru.
Root tangle or similar spell, prestidigitation to ignite oil containing sword (dont even have to have legit enchantment) attack
Next turn fighter does what fighter does. (Yes next turn specifically because a martial artist who bothers to learn magic is going to bother to get various advantages that will guarantee certain strategic advantages like initiative)
You're assuming the opponent has powerful spells left at their disposal. It also depends on whether or not the fighter makes their save. Just like my dwarf made his save and demolished the silly wizard who dared question the supremacy of martial types and got his ... hat ... handed to him.
Since my personal experience is the only one that matters, I say fighters rule, wizards drool. Or ... it just depends on the rules used, and half a dozen other circumstances. Given enough encounters without chance to recover spells they balance out. Just as important, they tend to fill different roles in the party and one is not "better" than the other.