Flying Dice I am not sure you even read western comics if "When one of the primary resons for a character to exist is to be sexy" is actually what you believe the majority of female characters are.
While I do think unjust fanservice is overly rampant, I can seperate a "Fanservice character" and "A character doing fanservice" and a "Character overly sexualised to the point of Fanservice" as they are important/vital distinctions.
Most characters are written as characters first and then through the process of drawing them they often go "Hey, what if we maker her breasts huge, make her hips curvy, and make sure she can only walk by sauntering".
Fanservice and "Sexual characters" are seperate in my mind.
I am seriously wondering who I am arguing with... Since I am getting very specific arguements that I have long since divorsed.
"It's not fanservice if they're always dressed like they're looking for a john?" Yeah, no
Temporal mistake you made... a rather large one. Let me correct you
"It's not fanservice. Why are you being turned on by a Dress John? Your mother wears that"
In otherwords certain looks start to become desexualised over time. You can see that happening RIGHT NOW with Bathing suits with certain styles being considered non-sexual that were considered extremely sexual 20 years ago. For example 6 year olds can wear Bikinis and Two peices without getting looks.
This is the process of Desexualisation.
Thus many of the costumes you have labled as being Extremely sexualised have long since, to people who read comics, been desexualised. Sometimes this means they go for even sexier costumes (As is, unfortunately, often the case for Catwoman) and sometimes they just don't change it.
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Though yes as I say... Anime looks at that and goes "Please, we can do better. Watch as we create sexual tension between 12 year olds as one beats the other with a crop."