"Lord of the Rings was written as an allegory for salvation history. Tolkien said as much and was a devout Catholic who had a close friendship with the great theologian, C.S. Lewis. It's not comparable."
Could you perhaps prove that? Tolkien was a devout Catholic but he also wrote quite emphatically that Lord of the Rings was *not* an allegory for anything though people have tried to connect it to Christianity, WWII, WWI, nuclear weaponry etc etc etc...
"The story is neither allegorical nor topical."~J.R.R. Tolkien
Something to note in Tolkien is that Elves, who are not human, use stuff that humans call "magic", but the Elves find the term puzzling, since to them it's not magic but technology.
At any rate, there's not much human magic and sorcery going on, which from a theological standpoint is actually rather important.
Gandalf and Sauron are actually angels. Of course angels have powers men don't have, for good or ill, and can use them.
Elves are a different species from humans, with a different creation. Elves aren't necromancers, but even if they do practice "magic", such magic is inherent to their natures. The Bible speaks to men, not Elves (or bats, which use mysterious sonar to find and trap bugs, or electric eels, who use their own form of "magic", natural to them).
It's not that angelic powers or the fact of being a spirit is not ok. It's that it's not ok for humans to boost their natural powers by trying to harness spirits. That's why Tolkienian magic does not fail the Christian test.
The magic in it is not human but Elvish or angelic.