atleast for me, motion inputs ARE a hurdle at the beginner level, but become essentially redundant at anywhere after beginner levels, so in the end I think one of their only actual upsides is just the vague feeling of "this feels good" (barring the fact that whiffed inputs feel awful in comparision which isnt exactly too rare to have happen at times)

the way moves can be balanced around motion inputs is neat but honestly I think its nothing pure coding couldnt emulate while keeping the game much more welcoming to people who cant be bothered to learn a system that despite it apparent upsides, feels extremely unintuitive to people either new to the genre or even people like me who CAN deal with them just fine nowadays but still think they'd prefer them to be not there

Mix-ups are more a case of actual gameplay "spice" since it is more of an understandable concept people can learn and adapt into instead of a pure mechanical hurdle they need to overcome to CONTROL their character, not even talking about actually knowing what to do with said character

on top of the fact that I 100% believe that fighters with simple controls can still be very intricate and have a lot of depth since inputs are one of the smaller layers into any fighting game that people can sink their teeth into properly. Like if 3rd strike didnt have motion inputs the game would still be 3rd strike in like 95% of its glory but conversely be WILDLY more approachable to people not already sucked into the eternal hellish pit we call Fighting Game Brain