The actress shared new remarks on the issue Tuesday night during a SAG-AFTRA panel where she was present and given the floor to air out her thoughts. It's interesting ... MR doesn't address her own snub for Best Actress, but she does explicitly defend Greta Gerwig.

Margot says, "Obviously, I think Greta should be nominated as a director, because what she did is a once-in-a-career, once-in-a-lifetime thing, what she pulled off, it really is. But it’s been an incredible year for all the films."

She went on to say that she's "beyond ecstatic" that 'Barbie' racked up as many nominations as it did (8) -- but in the same breath, noted she understood the disappointment from fans.

Margot finished by saying ... "I just suspect it’s bigger than us. It’s bigger than this movie, it’s bigger than our industry." Unclear what exactly she means by that ... sounds like she's referring to politics within the Academy, though.

Last thing Margot mentioned on this topic ... "We set out to do something that would shift culture, affect culture, just make some sort of impact. And it’s already done that, and some, way more than we ever dreamed it would. And that is truly the biggest reward that could come out of all of this."

Remember, there was widespread outrage over the fact Margot and Greta had been left off the nominations list -- even though Ryan Gosling and America Ferrera got Oscar nods.

Many felt if Ryan was nominated, it was a no-brainer to get Margot in there too ... seeing how she literally carries the film, and is the heart and soul of the whole thing.