You are correct that it means they expect margins to increase. One possibility is that ARM has higher margins as you mentioned. Another is that they are making some assumptions about how much they can reduce certain expenses by, and once you factor in those savings, margins go up.
I would guess they do have higher margins since they are mostly selling licenses and not actual hardware.
This article is old, but suggests a 48% operating margin: https://asia.nikkei.com/NAR/Articles/ARM-posts-strong-profit...
EPS -> earnings per share
Non-GAAP -> doesn’t follow generaly accepted accounting practices. There are alternative accounting methods. GAAP is very US-centric (not good or bad, just stating a fact).
Though note the intent of GAAP is to cut down on "creative accounting" which can tend to mislead.
Can someone explain this? (From the bullet points of the article)
I looked up the definition of accretive: "characterized by gradual growth or increase."
So it seems like they expect this to increase their margins. Does that mean ARM had better margins than NVIDIA?
Edit: I don't know what non-GAAP and EPS stand for