Sorry, but, how do you know whether Mika was popular or not? What evidence do you have? Because there's plenty of evidence of her popularity.
"44 fan favorites"? Characters like T. Hawk, Dee Jay, Gen, Rufus, Adon, Honda, and Fuerte consistently do poorly on polls. Do you really think Gen is more popular than Mika? Honest question. Do you REALLY think Gen is more popular than R. Mika? Adon? T. Hawk? Come on.
Capcom straight up admitted that Adon was put in SF4 even though he wasn't popular. So, don't use inclusion in SF4 as evidence of relative popularity. Birdie in SF5 says hi.
Meanwhile, Mika consistently does well on polls, and it's dismissed because "well, she hasn't been in any games recently, so that's inflating her popularity". You know who also hasn't been in any games recently? Joe, Mike, Retsu, Geki, Twelve, Lee, Sean, Eagle, Necro. These characters do horribly in polls. Funny how these characters don't get the "haven't been in any games recently" rub, too. Almost as if Mika is MUCH MORE POPULAR THAN THEY ARE.
Should I bring up fan art? And how she gets a lot of it, in spite of only being in one game? (I'm talking pre-SF5 reveal. Now, she's getting EVEN more.)
Mika is released and makes arguably the biggest splash of any SF reveal EVER...trending all over the world on social media. But, she's not popular?
Okay.