Because DnD is such a high power level fantasy world, much higher than what alot of other fantastic worlds depict, and outside of anime they typically don’t have very sharp power curves, Gandalf while revered in his universe, is very small potatoes compared to some of shenanigans that a DnD wizard can achieve
Mundane Fighters really don't fit the 'level' of DND, they belong in lower magic settings like Westeros or Middle Earth where magic users are also much more restrained, or are more limited by cast times, or at the very least where armies they can lead at higher level are a more important part of stories.
Gandalf literally sang the universe into existence with his brethren. No D&D wizard ever did that. And one of Gandalf's siblings moves the sun through the sky, and another the moon. Yet another raised Numenor from the sea floor and raised it up as a island nation and fastened another island to the sea floor when it reached Aman. Melian another like Gandalf shrouded an elf nation such that not even Morgoth could find it and her daughter who was half-Maia, was able to use her power to overcome Morgoth and put him to sleep. Gandalf is one such as them and has a great deal of power that he didn't show, because he was instructed to limit himself while in Middle Earth. He is NOT 6th level.
Something, something, major illusion because you want to abandon the party before things get too difficult, something.
Generally, when people talk about Gandalf's power they're discussing things he did on screen during the novels when he was in an adventuring party, like throw flaming acorns at wolves who would have killed him had the eagles not bailed him out.
So if Elminster was in a book and all you saw him do was cast several fireballs, toss a few lightning bolts, etc., he'd be low level as well? Gandalf did those things.
Sounds like the GM forgot to vet gandalf’s backstory before approving the character.
