I guess it depends on whether you are trying to “sell” Defold to people, or rather give people a hands-on intro tutorial where you explain difficult concepts.
If it’s more the first one, I recently did a survey among the community where I asked quite generally what people thought about Defold. For example, to the question “Out of Defold’s features, concepts, etc – which three do you value the most?”, the three which stood out from the others were 1) the amazing community, 2) it’s completely free, 3) performance/cross-platform aspects.
A lot can be said about 3, as well. Is it performance regarding the Defold user’s game development/workflow? In that case, Hot Reload, stable engine/editor and fast builds might be good things to mention. Performance regarding the games that are build? Then maybe the “no bloat” architecture, small build sizes are things worth pointing at.