When it comes to new ArM players it seems like it might be easier for those with experience with other games to overcome the initial hurdle of learning enough of the rules to get started. This certainly makes sense as there are some concepts that are shared by most RPGs. The idea that you play a character who is represented by numbers and descriptions and that you roll dice, trying to beat some target number, for example, will be familiar to experienced players.
However, I wonder whether this discussion is overlooking the fact that some of the differences between ArM and other games may trip up these experienced players because their expectation of how an RPG "should" work don't align with how ArM actually works. An experienced D&D or PbtA player may well be confused how this is all supposed to work in actual play. Someone who is completely new to RPGs at least doesn't have any old habits to unlearn.
Should we be more mindful of the audience and consider different approaches to introducing ArM depending on their background? For example, a (gentle) introduction for completely new players vs. an introduction for D&D players vs. an introduction for players of narrative games.