It has an aspect of, "You ignore all class, race, spell and level requirements on attuning to or using a magic item."

I'm curious, does this impact alignment limitations?
Also some items have post attunement bonuses.
ie. Axe of the Dwarvish Lords has extra bonuses if the character is a Dwarf.
If the Magic Item Savant ignores all case requirements on attuning, does that mean they gain the benefits as if they were a dwarf?

Or Mind Blade which requires attunement by a specific individual. I suppose Mind Lash which requires attunement by a Mind Flayer is possible.

Additionally, Theros has some artifacts with more unique attunement requirements like worship.
Khrusor, Spear of Heliod, "If you aren't a worshiper of Heliod, the spear has 2 randomly determined major detrimental properties."
Does the Artificer also ignore this aspect as well.

I think it would be cool to have an iconoclast who can use the god's weapons against them and they have no means of punishment (i.e. detrimental effects, not sending out a champion to attack the Artificer)

The ability does exactly what it says it does.  It does not give you other bonuses.  It does not let you get around attunement restrictions beyond class, race, spell, or level requirements.  The Axe of the Dwarvish Lord's bonuses to dwarven wielders is not an attunement restriction, therefore Magic Item Savant does nothing.  Likewise, the various Theros magic items that are restricted by what god you worship are ineligible for MIS because that's not something that it works on.