Does truesight + the Detect Magic spell defeat the Nystul's Magic Aura spell?

Question

Suppose I suspect that an object is magical. I cast Detect Magic, but I see no magic aura on it.

However, I'm still suspicious, and now I begin to suspect that the aura has been hidden by Nystul's Magic Aura. I happen to have a Gem of Seeing, so I activate it and then once again use my action to see magic auras while peering through the gem at the suspicious object, this time with the truesight granted by the gem, which among other things allows me to "automatically detect visual illusions".

Will the combination of truesight and Detect Magic allow me to see a magic aura hidden by Nystul's Magic Aura, or at least allow me to perceive the presence of an illusion?

Answer 1

No, Nystul's Magic Aura still works against truesight and detect magic

Part of what Nystul’s Magic Aura does is make “divination spells reveal false information about it.” Both Detect Magic and True Seeing are Divination spells, so they reveal false information – separately or in combination.

In the case of a creature whose truesight does not come from a spell, as in the example of a Gem of Seeing, this also doesn't work. Nystul’s Magic Aura does not create a "visual illusion" that truesight can detect – it specifically misdirects "divination spells", not visual senses.

Similarly, for a creature whose ability to detect magic is not spell-based, Nystul’s Magic Aura changes the way the target "appears to spells and magical effects [...] that detect magical auras".